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1 2 3

MICTOCOrV KtSOlUTION TfST CHART

lANSI onj ISO TEST CHART No 2)

^ ^PLIED IIVMGE

165J Ea?t Mam Street

Rochester, Ne« rork U609 USA

('16) «82 - 0300 - Pttone

(716) 288- 5989 - Fom

CANADA

DEPARTMENT OF MINES

Hon. LouiB Codwihi, Minister; A. P. Low. Deptfty MinUtor

GEOLOGICAL SURVEY

R. W. Bbock, Director.

MEMOIR 19

No. 26. Gi£OLOQICAL SERIES

Mother Lode and Sunset Mines,
Boundary District, B.C.

O. E. LeRoy

VORK

OTTAWA

aovssNiiBNT ptasTma bubkao

1913

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CANADA

DEPARTMENT OF MINES

Hon. Leva CooMHi. MiaUtor; A. P. Low, Dnuty UmUtm,

GEOLOGICAL SURVEY

R- W. Broi'k, Dirrrtor.

MEMOIR 19

No. 26, QEOLOQICAL SERIES

Mother Lode and Sunset Mines,
Boundary District, B.C.

»r
O. E. LeRoy

OTTAWA

OOVKRNUBNT PRIN1..(0 Bl'RKAU

IBIS

N.. UM.

CONTENTS.

CHAPTER I,

Introiturtinii

(icni ml •tnti'mcBt. ,. ....'''
f l.'lil >v.,rk itnil nrknowledffmrnta

nltuntion

Hinlory

Prvviuua work nn'l Ijibliojcrnphy., .

CHAPIEK n.

Ocnrnl I'tmrnrtor of <listriet,

Topo«iaf)hy

Ki'Kiimal

Loi-iil

Cliniate anil flora

CHAPTER in.

Ptot

I
I
>
I
S

General giiiloKy

UcniriU (l< .rription ut (ornmtioM

I'nl:ii,/i,ic: ■ ' •

Mi'wijoic •■••■

Tcriiiirj- . '.'.'.'.'.'.

•.'iiutcrniirv .'.....,..'

'I ilili' i>f r>rinatinnfi.

( oiiipHnif ly. ul,|. , Oiwlwooil an.i I'hoonij '.'..". ?

lJi'taili'<l ciiiMriiili.inof (oniiatioiw

Palu'ozoir ..,.,,

Knoll Hill Group .'....'............',

Intrniiurtion ' ■ ■

Uistril.ution iin<l »tructure. !.....

Lithc>lr)tfy ■ ■

Jii^piroiils

f'hirta

Tull> '.'.'.'.['.'.".

Brooklyn fonimtion

IntHxIuciiun , ...... I-

r)i^.tril)Ution and structure. . il

Litl.ol.iKy }J

Ci 1 iiiical roiiipoaition }5

Quarti |»)rpliyrite '.'.'.'..'.'.

13
13
13
13
13
13
14
U
15
1«
17

Mt'sojoic

luni ou» rork.f

Intnnliiction

Grunodioriti-^roup

l)i<lriliuiion

Litliolo^fy

IIornMi mil- porphyrite

TertLiry

IguttmH ror-kw

Ititrtxiut'fion

Lit!iol<)b;,\'.

Olivine l)a.-ialt

AuKili' porpliyritc ..',.... S

Monzonitc porplivry.... si

Pulaskit,. porphyry .'.'.■.■.■.'.■.'.■.■,' S

Quaternary °V

19
20
20

'fit
21
21
22
J4
25
25
25
26
26

CHAPTER IV.

Economic Kcolojfy

Ucadwood mineral xoo''

3938— H

32
32

CHAPTER IV-Co«tfnii«<i.

Introduction

Distribution

Geological relations

Character of ore bodies

Character of ore

Mineralogy

Metallic minerals.

Paoi
32
32
33
34
3S
36
36

Chalcopyrite 36

Iron pyrite.

Magnetite

Limonitc

Malachite

Non-metallic minerals

Actinolite

Tremolite

Garnet

Epidote

Zoisite

Chlorite

Calcite

Quarts

Origin of ore bodies

CHAPTER V.

Detailed description of mines

The British Columbia Copper Company

Introduction

Mother Lode mine

Location

Production

Development and equipment

Methods of mining

Geological relations and character of the ore body. . .

Character of the ore

The Sunset mine

Location

Production

Development and equipment

Geological relations and character of the ore bodies..

Character of the ore

Tlic Crown Silver mine

The Quclx'c Copper Company

Tlio Marguerite mine

Indcx

38
38
39
39
39
39
39
40

43
43
43
4S
4S
45
46
46
47
48
SO
SO
50
60
50
51
51
52
52
53

ILLUSTRATIONS.

Map 29.^. Mother Lode and Sunset mines, topographical edition in pocket

" 30A. Mother Lode and Sunset mines, geological edition in pocket

Plate I. Mother Lode mine, 1910 Frontispiece

" II. (A): Shows characteristic topography of the Boundary district.

Phoenix upper right and Greenwood lower centre; (B):

Brecciated limestone in the mineralized sone. 6

" III. (.\): Limestone in part replaced by silica; (B) ; Limestone in

part replaced by epidote and quartz 14

IV. (A): Glory hole (in part) Mother Lode mine, 1910; (B): Quartz

veinlets traversing a partially silicified tuff 3.^

" V. (.\): Garnet crystals in calcite; (B): Chalcopyrite in actinolite.. o6

Fin. 1. Index map 2

" 2. Map showing distributionof granodiorite in the vicinity of the Mother

Lode mine 21

" 3. Claim map. Mother Lodemineand vicinity 44

THE MOTHER LODE AND SUNSET

MINES, BOUNDARY DISTRICT.

BRITISH COLUMBIA.

CHAPTER I.
INTRODUCTION.

GENERAL STATEMENT.

The Boundary district for the last eleven years has been the
most important copper prof'ucing district in British Columbia
and for several years has held the leading position among the
copper producing centres of Canada. In the first decade (1900
to 1909) of production in the Boundary the copper content
in the ores mined amounted to 247,995,303 pounds, the metal
also containing important amounts of gold and silver as by-
products.' The production in 1910 amounted to 31,354,985
pounds of copper based on smelter returns.

The principal mines which are producing the typical low grade
and almost self-fluxing copper ores in the Boundary district
are the Knob Hill-Ironsides, Gold Drop, Rawhide, Snowshoe,
Monarch, and War Eagle situated at Phoenix; the Oro Denoro
and Emma at Summit ; and the Mother lode at Deadwood
near Greenwood (Fig. 1, p. 2). The controlling companies
operating the above mines are the Granby Consolidated Mining,
Smelting, and Power Company Limited; the Consolidated
Mining and Smelting Company of Canada; and the British
Columbia Copp^ r Company Limited of New York.

The present report is devoted to a descripi ion of the geological
relations of the ore deposits of the Mother Lode, Sunset, and
adjacent properties at Deadwood, and is an extension of similar
work previously carried on at Phoenix in 1908.'

'.Annual Reports of the Minister of Mines for British Columbia 1900 to 1910.
Mcmdr^No.'2?; ^" ^^^°^ ^^ °'* Deposits of Phoenix. Geol. Surv.. Canada,

FIELD WORK AND ACKNOWLEDGMENTS.

The area mapped is about two-thirds of a square mile in
extent and includes the Mother Lode, Sunset, Crown Silver,
and Marguerite mines (Fig. 3, p. 44). Both topographical and
geological work were carried on simultaneously during Septem-
ber, 1910. The topography was in charge of Mr. W. H. Boyd
and his assistants. The areal geology was undertaken by Mr.
C. W. Drysdale, while the writer devoted his time to the study
of the ore deposits and their geological relations. The map is
titled the Mother Lode and Sunset mines, named after the two
most important mines. It is published on a scale of 400 feet
to an inch with a contour interval of 20 feet.

Acknowledgments are due to all the officials of the British
Columbia Copper Company, particularly to Mr. J. E. McAlli-
ster, Mr. F. Keffer, Mr. E. Hibbert, and Mr. A. Burnett for
their courteous co-operation in connexion with the various
phases of the work.

SITUATION.

Deadwood camp, with the Mother Lode mine as an arbitrary
centre, is about 83 miles by rail from Greenwood and is about
3,450 feet above sea-level. It is about 12 miles north of the
International Boundary and about 6 miles from Phoenix where
the other more important mines are situated (Fig. 1, p. 2).
Greenwood, 117-3 miles by rail from Nelson, is situated on the
southern line of the Canadian Pacific railway, which leaves
the main line at Dunmore junction, and which is now being
extended to Vancouver through southern British Columbia.

HISTORY.

Gold was first discovered in Boundary creek, and placers were
worked as early as 1862. During the interval between 1862
and 1891 little attention was paid to the district and but few
claims located. In 1890, the Rossland gold-copper deposits
were discovered, and this apparently stimulated prospecting
over a wide area in southern British Columbia. During the
following year prospecting was actively carried on at Deadwood,

Phoenix, and other neighbouring mineralized areas in the district.
The prospectors came into the country by way of Marcus in
the State of Washington. A pack trail followed the Kettle River
valley and connected with the Dewdney trail at Grand Forks;
from it branch trails were built into the several camps by the
prospectors. In the Deadwood camp the Mother Lode was
located on May 23, 1891, by William McCormick and Richard
Thompson; the Sunset on June 2 by John East; and the
Crown Silver on the same day by William Ingram. These were
located under the old law which allowed claims to be 600 feet
by 1,500 feet with extra-lateral rights. This act was repealed
in 1892 when the present law was established allowing claims
1,500 feet square with vertical side lines. Practically the whole
area in the vicinity of the above claims was staked during the
subsequent years. In the first few years the same disappoint-
ments were experienced by the prospectors at Deadwood as
by those at Phoenix. The ores were found to be of a very low
grade, though the bodies were apparently of large size. The self-
fluxing qualities of the ore were only discovered at a later period
when subjected to met illurgical tests.

The history of Deadwood hinges altogether on that of its
premier mine, the Mother Lode. It was bonded in June, 1896,
to Colonel John Weir of New York, and in 1898 became the
property of the British Columbia Copper Company. Extensive
developments were planned and carried out, preparations were
made for the construction of a smeltery at Anaconda — which
adjoins Greenwood to the south — and a spur was built from the
Columbia and Western railway at Greenwood to the mine.
The latter was completed in 1900 and the first furnace of the
smeltery was blown in early in that year. Since then the
Company has gradually expanded, both by increasing its holdings
of mining properties and by enlarging its smelting and converting
plant which is now capable of treating about 2,400 tons of ore
per day. The Sunset and Crown silver mines were sold in 1897,
and after passing through the hands of several companies, a
re-organization was effected in 1909 whereby the holding com-
pany, known as the New Dominion Copper Company, passed
under the control of the British Columbia Copper Company.

The total production of the mines at Deadwood up to the
end of 1910 is probably not less than 2,114,481 tons of ore
though exact figures are not available. Of this amount 2,014,481
tons are to be credited to the Mother Lode mine.

PREVIOUS WORK AND BIBLIOGRAPHY

Mr. R. W. Brock of the Geological Survey staff made a recon-
naissance survey of a portion of the Boundary district in 1901,
and during the following year geologically mapped a belt about
13 miles wide along the International Boundary, extending from
Grand Forks west to Midway. Dr. R. A. Daly, geologist to
the Boundary Commission, at a later date, geologically exam-
ined a 5-mile belt a'ong the International Boundary, the results
of which have not yet been published.

The following reports and papers bear directly on the geology
of the Boundary district, and on the mining and smelting in-
dustry at Deadwood and Anaconda.

Brock, R. W The Boundary Creek District:

Summary Rep., Geol. Surv., Can.,
1901, pp. 5-69A.

Preliminary Report on the Bound-
ary Creek District. Sum. Rep.,
Geol. Surv., Can., 1902, pp. 92-
138A. Map No. 828.
Ore Deposits of the Boundary Dis-
trict. Jour. Can. Min. Inst., Vol.
5, 1902, pp. 365-378.

Daly, R. A Geology of the North America

Cordillera at the Forty-ninth Par-
allel. (To be published by the
Boundary Commission.)

Emmons, S. F The Ore Deposit of the Boundary,

B C. Genesis of Ore Deposits,
1901, pp. 759-761.

Hibbert, E Methods and costs. Mother Lode

Mine, Eng. and Min. Jour., Vol.
95, No. 12, 1913, pp. 559-601.

Keffer, F A Method of Mining Low Grade

Ores in the Boundary District, B.
C. Jour. Can. Min. Inst., Vol. 5,
1902, pp. 213-216.
Mining and Smelting in the Boun-
dary District. Jour. Can. Min.
Inst., Vol. 7, 1904, pp. 42-46.
Notes on Diamond Drilling in the
Boundary District. Jour. Caii.
Min. Inst., Vol. 9, 1906, pp. 317-
320.

Notes on the Cost of Diamond
Drilling in the Boundary District.
Jour. Can. Mir. Inst., Vol. II,
1908, pp. 385-391.

Ledoux, A. B The Production of Copper in the

Boundary District, B.C. Jour.
Can. Min. Inst., Vol. 5, 1902, pp.
171-178.

McAllister, J. E The Greenwood Copper Smelting

Works. Eng. and Min. Jour.,
May 20, 1911, pp. 1011-1015.

Mcintosh, M. D Mining Methods and Equipment

at the Mother Lode Mine. Jour.
Can. Min. Inst., Vol. 12, 1909, pp.
437-450.

Reports of the Minister of Mines, British Columbia. From
1894 to 1910.

Stokes, Ralph Mines and Minerals of the British

Empire. Chapter 23, pp. 244-355.

Weed, W. H The Copper Mines of the World,

pp. 217-220.

Ore Deposits near Igneous Con-
tacts. Trans. Amer. Inst. Min.
Eng., Vol. 33, 1902, pp. 715-747.

Wickware, F. G The British Columbia Copper

Company's Mines and Smelters.
Jour. Can. Min. Inst., Vol. IX,
1906, pp. 333-360.

I'UTI li.

A. PhotoKraph shows chaia. Uiislie tupograpliy of tliu Bouniiiirj- ilistrict. Phoenix
in the upper right corner, Greenwood lower centre.

B. BrecciHted limestone in the mineralijed lonc being replaced by garnet cpidotc, etc.
3938-p. 7

CHAPTER II.
GENERAL CHARACTER OF DISTRICT.

TOPOGRAPHY.
REGIONAL.

The Boundary district of British Columbia as far west as the
Kettle river lies within thr Columbia system of the North
America Cordillera.' This system has been divided into a num-
ber of groups, bounded, as a rule, by the more important minor
valleys. The Midway mountains form the group which includes
that portion of the Boundary district lying east and north of the
mo\n Kettle river, and west of the North fork of the Kettle
(Fig. 1, p. a). This group is characterized by comparatively
low mountains, which, when broadly viewed, appear as rounded
ridges and dome-shaped summits, with crests at an average
general elevation of 5000 feet above sea-level (Plate II, A).
The valley system is well developed; the main or longitudinal
valleys are relatively broad and U-sbapcd with their sides usually
flanked by series of terraces which may reach an elevation of
2000 feet above the valley floor. The tributary or transverse
valleys are V-shaped and their streams usually flow with steep
gradients, often entering the main valley with abrupt change in
grade. Plate II A shows the town of Greenwood in the fore-
ground, situated in the U-shaped valley of Boundary creek, into
which flows Twin creek occupying the V-shaped valley running
up to the Phoenix basin.

The well wooded portions of the district occupy the northern
slopes of the ridges. The eastern and western slopes may be
either forested, or open and park-like, while the southern dopes
are more often open and grassy. The higher ridges and narrower
valleys are better watered and are usually densely wooded.

A low precipitation characterizes the district as a whole,
and to ensure success in agriculture, irrigation is generally neces-

'Daly, R. A.— The Nomenclature of the North America Cordillera between the
47th and 53rd parall..s of latitude. The Geographical Journal, vol. 27. 1806. dd.
586-flOfl.

sary on the bottom lands and imperative on the benches or ter-
race lands. Grains, fruits, and vegetabK's under proper condit-
ions of tillage give abundant crops, and an ever expanding
market for all farm products affords every encouragement for
the rapid development of the agricultural resources.

LOCAL.

That portion of Deadwood embraced in the accompanying
map, is situated on the southern slope of Deadwood ridge which
has a southeast trend and lies between Boundary creek and the
Deadwood-Copper Creek valleys. The ridge gradually rises
to the northwest and attains a maximum elevation of about
4860 feet above sea-level where it joins the Copper Mountain
ridge. The range in elevation in the area comprised by the map
is about 700 feet, rising from 3180 feet above sea-level in the
south, to a maximum of nearly 3900 feet along the northern
border. The subordinate spurs from Deadwood ridge in this area
are rather flat topped, and present rounded blunt extremities,
or their continuity may be broken by small valleys or depress-
ions which roughly parallel the main iidge. While irregularities
of surface give a relatively subdued ruggedness to the hilly
portions, the whole is comparatively rolling with a gradual rise
to the no'th. In the southwest, Deadwood creek occupies a
rather sicjp walled valley and is the only permanent stream.
The other streamlets are now of the intermittent, wet weather
typf 'lue largely to the deforestration of their drainage basins.
Deadwood drains into Copper creek, which empties into Bound-
ary creek at Anaconda, south of Greenwood.

CLIMATE AND FLORA.

The climate on the whole is an agreeable and healthy one,
though for short periods there are extreme ranges both in heat
and cold. In summer the days are hot, but are usually succeeded
by "ool nights. At Midway, 7i miles to the south, witli an
a' 'e about 1600 feet lower than Deadwood, the mean tem-
pt. . .es from 1896 to 1902 were 20-5"' F. for January, and

65* {or July. The annual mean was 43°. The moan precip-
itation at Midway for the years between 1894 and 1902 amounted
to 12-7 inches per annum. The Deadwood area was originally
rather well woodeH, pine, tamarack, fir, and spruce being the
most important trees. The demand in recent years for wood
for mininK and building, and the destructive forest fires have
reduced the reserves to low limits. Pr«-*ions of the area are
covered with a scrubby second growth, *hich also has been
recently burnt over in part.

CHAPTER III.

GENERAL GEOLOGY.

GENERAL DESCRIPTION OF FORMATIONS.

PAL/€OZOIC.

The oldest rocks in the map-nron conRi^t of a series o' iKncous
oriKu. Tlio r..(ks are mainly tufTs aiul fine n.h rocks, which
have been partially or wholly replaced by silica RivinR a series
of ••hcrts, and jaspcn.ids. The term Knob Hill ^roup is retained
for In. serus as the rocks in the main correspond to those
Bumlarly Rrouped at Phoenix. In this area, however, some of
the jaspero.ds have no doubt been formed by replacement
of the Urooklyn hmestone, but as it was not possible to s.-parate
these from similar ro.ks of the Knob Hill group they have been
mapped under the latter. No .lefinite position has been given
to the Knob H.ll group, but as no stratigraphical bnak was
noted ,t is possible that it is in the main but little older than
the Brooklyn limestone. The sueceedh.g formation is the Brook-
lyn, b..ing the lower member of the Attwood s.Ties. It consists
of grey to white non-fossilif.Tous, crystalline limestones, and has
been referred tentatively to the Carboniferous by Da'v from
rosemblanres to similar rocks in the Rossland mountains.
I he limestone is important because in it are the low grade
copper deposits occurring in a mineraliz.d zone of contact
metamorphism characterized by the extensive development of
lime silicates such as garnet, ei)idote, and actinolite.

Quartz porphyrite oeeurriiig in irregular dyke^ and small
masses cuts the rocks of the Knob Hill group a. :> the Brooklyn

formation. Tho rork in concidcrnbly nltertd ami to nome rxtrnt
h:is Hhiired in the Hilifificntion wliicli hu^ [ifToit.Ml thi- formnlions
it intrudes. The time of intruxion in placed proviHionully as
upper I'aluHjzoic, hut nuiy be Muiozoic thougli eurli«'r than the
grunodioritc of Jurassic (?) age.

MESOZOIC.

The granodiorite of Jurassie (?) age outcrops at neveral points
and occurs in undergn-und workingM, an dyke.s and inatises seem-
ingly connected will: a l.irger mass underlying the whole district.
It is widc-spreud thruugliout the district and large areas outcrop
in the vicinity of Deadwood (Imr. 2, p. 21). It ran-es in compowi-
tion from granite to HKmzonite, granodiorite being the prevailing
type.

Hornblende porphyrites in a few dykes and small masses also
intrude the ohler rocks. Owing to the few exposures they are
not seen cutting the granodiorite, but it is pussible that they
belong to ♦he Phoenix volcanic group of Daly, which is referred to
late Alesozoic. They arc so placed here provisionally.

TERTIARY.

The Tertiary is represented by a series of intrusivcs ranging
from olivine basalts to pulaskite porphyry. They occur in
dykes and .-ills, and theonh'r of intrusion, commencing with tlie
Idcst, is i)li\ine basalt, aupte purpliyrite, monzonitr^^ porphyry.
and pulaskite porphyry. They are referred to the Miocene
and are probably intrusive equivalents of the lavas of thr >rUhvay
volcanic uroup, which latter is (hvclopcd in the immediate
vicinity though just beyond the bordirs of this particular area
(Fig. 2, p. 21).

QUATERNARY.

The Cordillera ice sheet covered the whole area, the general
direction of movement being S. 18° E. The drift is modified
and consists of clays, sands, and gr.'ivcls with rounded bouhh'rs,
distributed as a mantle of varying thickness over the greater
part of the area.

TABLE OF FORMATIONS.

For purposes of comparison a tabular arrangement of the
rock formations at Phoenix and Dead wood is given, following
the table of formations for Dead wood.

Quaternary. Glacial and Kcrcnt . . Modified drift, ctays, sanda, gravels.

Tertiary Mioccner Pulaskite porphyry.

(alkali syenite porphyry).
IJ>yke8 and sills.

Honzon:te porphyry.
Dyker and sills.

Auidte porphyrite.
Dykes.

Olivine basalt.
Dykes.

Mesozoir Hornblende porphyrite.

Dykes and masses.

Jurassic? Granodiorite.

T Quartz porphyrite.

Paleozoic, Carboniferous? Attwood aeries, Brooklyn formation.

Ciyatalline limestone.

Knob Hill group.

Tufif and ash rock more or leasailicified, chert,

jasperoid.
Sniall leniies of argillito and limeatone. Group

m part is silicified limestone of the Brooklyn

formation.

COMPARATIVE TABLE OF FORMATIONS.

Period.

Dead wood.

Phocniz.

Miocene I^ilaskito porphyry Pulaskite porphyry.

Monzonitc porphyry

Augite porphyrite Augite porphyrite.

Olivine basull

( )ii„„„,.„„ Midway volcanic group(LavnK)

'"*-"""' ■. ,i ■ ■ , , , ^^Pttle River formation.

Jurii.^sic

('ftrl>oniferou.i

I'ri>("arl)oniferouH

Hornblende porphyrite

(iranodiorite group Syenite and syenite porphyri'.

Quartz porphyrite..

,, , , , Rawhide formation.

lirooklyn formation Brooklyn formation.

Knob Hill group Knob Hill group.

DETAILED DESCRIPTION OF FORMATIONS.

PALEOZOIC.

Knob Hill Group.

INTRODUCTION.

tuffs, together with small residual masses or lenses of argillite
and crystallme limestone. The rocks belonging properly to the
group were, in the main, originally tuffs of varying texture
usually extremely fine grained. These have been altered wholly
or m part to such hi^ghly siliceous types as cherts and jasperoids.
Part of the jasperoid at least is replaced limestone of the Brooklyn
formation, but has been arbitrarily included in the Knob Hill
on account of its intimate association with the roi" s of that
group. Other residual masses of limestone and of argiUite
may possibly belong to the Brooklyn and Rawhide formations'
infolded in the tuffs, but any decision to be regarded as final
must await more work in other fields where the relations are
nriore clearly shown. In the Phoenix area the jasperoid zone is
sharply marked off from that of the cherts, but at Deadwood
there is a gradual transition between the two, and in mapping,
the boundaries have been somewhat arbitrarily drawn, dividing
zones of jasperoid-tuffs from those of chert-tuffs. The age of
the group is Palaeozoic without any definite position being
assigned though it is probable that no great time interval
lapsed between the deposition of the Knob Hill tuffs and the
Brooklyn limestones.

DISTRIBUTION AND STRUCTURE.

Tuese jasperoids, cherts, and tuffs probably underlie the whole

fhl ,rVT- lu' J^«P^^«''J« 'I'-e usually at a higher horizon
than the cherts. The rocks arc massive, rarely banded, and the
several umts occur as irregular lens-like masses, overlapping

M emdr^o.' ?i ^-°«^'°«' '"d Ore Deposits of Phocnii. Geol. Surv.. C.n., 1911

3938— i2

or dovotailinp; into one another sharply, or by pradual transi-
tions. They are much jointod and shcarcul in several directions,
the trend varying from N. 3° 11. to N. 08° E. with dips ranging
from 70° to 90°. It is probable that faulting has been general,
with possibly little displacement, but no data rcfiarding the
latter question could be gathered on account of the general
similarity of the rocks. Locally along zones of shearing small
areas of schists have been developed in the chert-tuff zone.
Along some of the later fractures which were avenues for the
Tertiary igneous intrusives, vertical and horizontal zonis of
brecciation occur, the fragments in part being cemented by the
igneous rock. Finer friction breccias occur in fault planes
noted underground.

LITH Vl.OGY.

J asperoids.— The jaspcroids are grey or greenish grey in
colour, and consist of oval, rounded, oblong, and subangular
pebble-like individuals of grey or brownish grey chert embedded
in a matrix of calcite, quartz, and chlorite. They weather to a
light rusty grey colour with the chert individuals standing out
in high relief (Plate IIIa) and often simulate in character a con-
glomerate or breccia. Veinlets of quartz and calcite fill joint
and other planes which commonly traverse the rock.

The individuals of chert vary from those of microscojiic
size up to others an inch or more in diameter, and on the whole
the rock is much fim - rained than the type occurring at Phoenix.
The matrix varies Irom an almost purely calcareous one, to a
dense quartz-chlorite type in which the chert individuals can
only be discerned with difficulty. In minute shear zones pyrite
and chlorite are usually associated, and the former in crystals
and grains is rarely absent from the main body of the rock.

Microscopically the chert individuals are seen to consist of
aggregates of niicrocrystalline or cryptocrystalline (juartz up to
13 mm. in diameter, the individual grains having either smooth
or interlocking borders. The grains show slight strain shadows,
and a development of catadastic structure in some of the
larger ones. The matrix varies depending on the origin of the
jasperoid. If it is derived from a tuff the matrix is composed
of compact kaolin felts in which lie fragments of feldspar, grains

I'r.MF n-

A Limoatonc in part replaced l.y silica, rcprpscnts a transitional typo bctii

hnifstonr and ja.six'ruid .

B. Limestone (1), in part replaced by cpidotp (c) and quartz (a)
3938-p. 14 '

of quartz, calcite, in small amounts, and ragged plates and
fibres of chlorite. If, however, the rock was originally a lime-
stone, th' matrix is largely calcite with numerous grains of
quartz, and shreds of chlorite. Trcmolite, epidote, garnet,
magnetite, and chlorite are present in the matrix of some of
those types associated with the ore bodies, and are believed
to be later metasomatic replacements of part of the calcite
matrix, in the zone of contact metamorpiiism.

The calcite is both clear and tuibid, occurring in mosaics of
grains or in sponge-like masses enclosing chlorite and tremolite.
The tremolite and chlorite usually occur in sheaf-like and radiate
clusters, and in minute acicular forms. The former is colourless
with a marked parting parallel to the base, and the latter is
pale green. The chlorite also fills a few minute shear planes
Pale yellow, turbid epidote and colourless, clear zoisite occur
in granular aggregates, or in single grains, either in the calcite
or along the contact of quartz veinlcts. Pale brown garnet has
similar associations, as also have the grains and crystals of mag-
netite and pyrite.

The jasperoid is traversed by a reticulating system of quartz
veinlcts with a width up to ' nun. Three or more periods of
vein filling exist, each period being separated from the succeed-
ing one by periods of minute faulting (Plate IV B).
The fractures and minute fault planes Acre ai)parently the
channels along which the .siliceous solutions travelled during
the period of replacement, and many of the veinlcts are of
tadpole form, and terminate in rounded individuals of chert.
In some types the pro.(>se.«, of silicification have progressed
more uniformly through the rock, and replaced it more exten-
.sively, giving gradual twinsitions between jasperoids and chert
in which there are few distinct individuals of the latter.

Cherts.— The cherts are grey, bluish, lifiht greenish, dense
grained siliceous rocks K(>nerally massive though occasional' r
bandedin various tones of grey. When locallv sheared they arc
cemented into qunrtz schists. They are finely jointc(' a-' "frac-
tured, with faulting and slight displacements. The p. .es are
filled with white quartz and occasionally with calcite. They are
brittle and have a conchoidal fracture. Near the ore bodies
the cherts arc dotted with flecks and grains of yellowish green
3938 — 2^

epidote. In the banded types narrow lensea or leaves of pyrite
have been deposited parallel to the banding. In appearance
they vary from a typical chert to a massive lode quartz or
fine grained dense quartzite. They weather from light grey to
almost white with ru3ty patches and streaks due to the decom-
position of the pyrite content. In the main they arc derived
from tuffs though some may have been originally argillites.

Under the microscope they are seen to be composed of grains
of microcrystalline quartz from 015 to 0-2 mm. in diametsr,
with smooth or interlocking borders, passing gradually into
vague areas of cryptocrystalline quartz which are usually turbid
from dark opaque (carbonaceous ?) films surrounding individual
grains or aggregates. As in the case of the jasperoids, the
cherts ar' traversed by a similar system of quartz veinlets of
three or more generations (Plate IV B). They have a radiat-
ing or parallel arrangement, and may swell out into lenses 2-4
wide and • 7 mm. in length with individual grains up to • 6 mm.
in diameter. Others occur as thread-like lenticular forms, pinch-
ing out in both directions along the length of the minute fracture.
Calcite in tiny grains is distributed interstitially through the
quartz; pyrite is usually present in grains and crystals often
surrounded by a narrow rim of limonitc; and near the ore bodies,
grains and aggregates of turbid epidote are sparingly developed
through the rock.

Tuffs. — The tuffs are fine-grained, dense, compact rocks and
in colour a dark grey usually with a greenish tinge. They are
finely jointed and fractured, the planes being filled with quartz
and occasionally calcite. Though generally massive, fine banded
types occur in alternating yellowish green and dark green
tones. They weather to a rusty grey with a finely spotted
surface.

Quartz, chlorite, feldspar, and pyrite are individual minerals
which can be distinguished in some of the coarser types. The
principal varieties are quartz-chlorite tuff, chlorite tuff, and
quartz-feldspar tuff. Microscopically, they consist of frag-
ments or individuals of twinned and untwinned turbid feldspar
and grains of clear quartz up to O-IS mm. in diameter, in a
matrix of microcrystalline and cryptocrystalline quartz, shreds

of kaolin, felty aggregates of pale green chlorite, vague and
turbid areas of calcite and epidotc, and grains and crystals of
pyrite and magnetite. The thin sections ali show additions
of secondary silica to a greater or less (- tent, indicating that
the rocks are in the nature of transitional 'ypes between tuffs
and cherts rather than true unaltered tuffs. Veinlets of
quartz similar in character to those described under jasperDids
and cherts traverse most of the thin sections examined (Plate
IV B).

The jasperoids, cherts, and tuffs, in the vicinity and adjacent
to the mineral zone or zone in which lime silicates have
been developed, contain epidote, zoisite, garnet, tremolite,
actinolite, and magnetite in trifling amounts. These minerals
are more abundantly developed where the matrix was originally
largely calcite and was, therefore, favouralile to replacement
by lime-silicates. Veinlets of calcite of a later period fill
fractures which cross the quartz veinlets.

The origin of the large quantity of silica necessary to convert
the tuffs and associated rocks to jasperoid and cherts, is not quite
clear. It may have been derived from some intrusive magma
possibly a deep seated body of which the quartz porphyrites are
offshoots.

Brooklyn Formation.

INTRODUCTION.

The Brooklj'n formation is the lower member of the Attwood
series correlated by Daly with the Carboniferous, from its
similarity to the rocks of that age occurring in the Rossland
mountains. In the map-area the formation consists wholly
of crystalline limestone, which, as elsewhere in the district, is
apparently devoid of fossils. It has been in part replaced by
silica giving ro;''- of the jasperoid type, and in part replaced by
lime silicates in a zone of contact motamorphism, or mineralized
zone, which contains the important bodies of low grade copper
ore (Plate III A and B.)

DISTRIBUTION AND STRUCTURE.

The main exposure of limestone occurs north of the Mother
Lode mine, while a larger area lies to the east of the Marguerite

mine, the western border of which appears on the map. Minor
outfropa occur at different points as residual masses lying in
the jasperoid and the mineralized zones.

The limestone has been associated with the rocks of the Knol
Hill grou)) in the various earth movements experienced since
their deposition, and the main contacts where they could be seen
appear to be faults, the limestone being block faulted down
into the tufaceoi;.- rocks, the faults in two instances being sharp
planes boundinj, the mii\eralizcd zone. A similar fault occurs
underground at the north end of the Mother Lode ore body and
the plane is followed by a dyke of augitc porphyrite. The
limestone is massive with the bedding planes obliterated. Irregu-
lar jointing causes the rock to break into rough angular frag-
ments. Near thi' ore bodies the rock is sheared and breaks into
tlat lens-like fragments coated with a thin fdm of chlorite.

LITHOLOGY.

The limestone is compact and crystalline throughout and
varies from medium to fine grained. The colour varies from
grey to pure white, the lighter types often having greenish or
bluish casts. The grey limestone in some localities may pass
sharply into the white, which on a fine scale gives a mottled
appearance to the rock. The white limestone is less compact,
and usually has a saccliaroidal texture. The rock is traversed
by an intricate system of minor planes of weakness now filled
by veiulcts of white calcite. Pyrite is usually present in minute
crystals and grains but generally is in very trifling amount.

Microscopically the rock consists of clear and turbid grains
of calcite with smooth and interlocking borders In mosaic
arrangement. Evidences of strain arc apparent in the uneven
extinction and curved planes of twinning and cleavage. Small
aggregates of microcrystalline and chalccdonic quartz are of
frequent occurrence even in the purest types of rock and are
developed interstitially to the calcite individuals, or tend to
replace the calcite along cleavage planes. Locally this replace-
ment of calcite by quartz unUer favourable conditions has con-
tinued until the limestone is wholly replaced, thus giving a
jasperoid, oc a rock having the appearance of a fine quartzite.
In an intermediate stage, the rock, transitional between lime-

stone and jaspcroid, i-onHista of oval and rounded, oblong urains
of light and dark Rny thcrt rniljodcUd in a matrix of light grey
crystalline limeatoni-. On the wcathiTcd surface the individual
grains stand out in high relief and simulate in ai)pear:tiiee
a line conglomerate. Further action in some cases causes the
grains to anastomose and form irregular areas of solid chert
an inch or !uorc in diameter, and in <'oiuplete replacement a
chert is the result in which tlie orifiiiial oval forms c;in oidy be
discerned on a polished surface or microscopically (Plate III A).
In piitces !i banding occurs where the jasperoid alternates
with limestone, tlie replacement by silica following more favour-
alile bands in the original rock. This is further ace tuateil by
the jasperoid being of dilVcrcnl grain in ditlVrent bands. Near
the ore botlies and along the border of the mineral zone, th-.-
limestone shows a spotted replacement by actinolite, garnet,
cpidote, etc., which have formi'd in little n' -ts interstitial to
the grains of calcite, or along the cleavage planes of that mineral.
The mineral zone is composed e;>sentially of lime silicates which
have replaci'd the limestone metasomatically. To prevent
needless repetition a description of this zone is omitted here
and appears under economic geology.

CIIF.MICAIi COMPO.SITION.

.\nalys( s of the grey and white limestones were made by Mr.
M. F. Connor of the Mines Hranch and appear below.

I ir Til

In>oIuI)lf 0;;2 OCO (140

(Ixidcsot iron :in(l :.luinir,iuin 1111) I'O 02(1

r;lli'iuiil (':ir!ii int.' a'l-Sti ',lli:i.-, 'J7-C7

Mzp^n. jiicii ciirliurKiti' l-'M> i ■ l.i 1-40

InditcniiinuJ, \vut( r. I'tn 2 4ii i:;.' 0:i:!

10000 lOOQO 10000

I. Wliitcfrystallinr linii-lunc. Mi'.rnU' riti' i.iinc.

II. Wliili'cry^<lallinc linu'-ii)ni', .Mot Ik r Uxlr mini', 200 fuot k'v( 1.

III. (jrcy crystallini' liiiu.-itoni', .Mar!;ucrit<^ iiiine.

Quartz Purphyrile.

Quartz porphyrite occurs in irregular dykes and small masses
intrusive in tho cherts and jasperoids of the Knob. Hill group,
and in the limestone and lime silicate zone of the Brooklyn
formation. The porphyrite in the field resembles some type.^

of the chert or tuff, though a close examination reveals its por-
phyntjc texture. The contacts arc usually definite in the lime-
stone areas, but much less so in the areas underlain by the tuffs
jasperoiils, and cherts. The rock is much jointed and sheared
and has beer, silicificd to a certain extent.

Macroscopically the rock consists of dull grey phenocrysts
of feldspar, and acicular and lath-like individuals of dark Rrrcn
hornblende, in a dense base composed chiefly of quartz. Under
the microscope the feldsjiar is seen to be very turbid from alter-
ation; it is in part twinned according to the albitc law. The
hornblende appears to be larRcly actinolite and is considerably
altered to chlorite. The base is a fine Mgregate of quartz and
turbid feldspar, through which is distril)utcd grains of calcite
and grains and crystals of pyrite. (Quartz veinlets are common
and are sinular to those occurring in the rocks of the Knob Hill
group (Plate IV B).

The age of these intrusions is not definite. They are post-
Brooklyn and pre-Jurassic and have been placed provisionally
in the upper Palaeozoic.

MESOZOIC.

Igneous Rocks.

INTRODtJCTION.

The Boundary district is apparently underlain, and at no
great depth, by a batholith of granodiorite and closely asso-
ciated rocks which outcrop generally throughout the district as
bosses, irregular masses, and dykes. The average rock is a light
grey biotite-hornblende granodiorite associated with granite
porphyries, and quartz diorite porphyries as closely allied types
More basic hornblende gabbro-like rocks passing into pure horn-
blende rocks also appear to belong to the same period. In
several localities the main rock type strongly resembles the
Nelson granite, which occurs east, north, and northwest of this
district. Many of the smaller masses and bosses are similar in
appearance to some phases of the monzonite intrusives in West
Kootenay.

_Thework on these plutonic intrusions has not been sufficiently
"Brock, R. W.-8um. Rep., Geol. Surv., Can., 1902, pp. 100-lOlA.

dctailpd to permit a decision being renehed in regard to the rela-
tions of the several types, whetlier they are differentiationH of
one intrusion or whether there wer.- severul periods of in-
trusion originating from one mngnm l)asin. No analyses of
these roclts haw so fur l.ecn published und none were made of
the types occurring in the map-area on account (. their not
bemg sufficiently fresh. The age of the batholith is referred
tentatively to the Jurassic period.

In the map-area there are small masses and dykes of
hornblende porphyrito which are as.Minied to be Mesozoic.
They have not been found in contact with the above
intrusives and their relative age has, therefore, not been
definitely decided upon. It is pos»;'.:.. that they may belong to
the Phoenix volcanic group „f Daly's classification, in which
case they can be referred tentatively to the later xMeso^oic.

w .'- H V << V ,

i r
> V .

1 f

■ r » ^ " ■- ► 4 .' > ►

K X it r. if-.

.H K \ u if.

, « r »; w ;; >;
K K » It i; ,- *

« « >: :

, U V K

Mother iedt

Sunitt

»Mar$u»rita

_ »■ ^

. ■•
» •» V 1 "'

* I. ^ H < -i ^ W
-iv «'

.•* I. ^ «: I. '•^ ^-^ J ,

.►»*:» 'r^ -iiy-'
. (- 4 <• -I '■^J •'►'• ► -'

*• -1 < I.

Oru finia

gd Oranodtarite Iv Artiary 2av<u

Fio. 2. Map BhowinR diatrihution of eranodiorite
in the vicinity of tho Mother Lode mine.

ORANODIORITE GROUP.

Dt«/n'6M<ion.— The rocks of the granodiorite group occur as
dykes and small, irregular masses which appear to be more

frcquont an' r in the lower li vrln of the mine workings.

They lire intrusive in ail tiie nxkn of tlie Paljeoasoie und arc
cut hy the Tertiary irruptiveit. In piaccn they have i)een
!tul)jecte(l to great alteratiiuw whieh have oixti-urcd their
liounduries to Honie extent.

Lithnhg If. --^Thf roeks vary within nioilenite limits in their
mineralogieal composition and also in their texture, hut they
may he hroadly classed uikUt ifranodiorite, monzmiite, and
quartz diorite. They have all a close similarity in ai)pearancc
in the field and in hand specimens. The texture ranges from
Kraiiituid with medium Rrain, to purphyritic with micronratiitic
Krinnidmass. The colour varies from liuht to dark prey with a
Krcenish tintje from the chlorite content, and the rocks weather
to a light rusty grey.

The feldspar phenocrysts are light and dark grey, in .some
cases pale pink, and vary in size up to 0-3 of an incii in
length. Bhu'k hornl)lende, pyrite, and magnetite can also he
distinguisiicd in hand specimens. Adjacent to the ore bodies
epidote, garnet, and calcite arc developed in limited amounts.
The rocks as a rule are mucii jointed, being traversed by several
systems, and in some cases are much .^beared. The planes are
filled with quartz, calcite and in the vicinity of the ore bodies,
by additicmal epidote, garnet, pyrite, and chalcopyrit ■ !- no
case are the rocks sufficiently unaltered for analysis as an the
exposures are adjacent to or in the near vicinity of the zones
of mine-'ulization and ore deposition.

The rocks consist essentially of feldspar, hornblende, and
quartz in phenocrysts or large individuals in a base of the same
constituents. Apatite and part of the magnetite are also
primary cimstitucnts. Chlorite, epidote, carbonates, quartz,
limonite, and part of the magnetite are secondary constituents
derived from the breaking down of hornblende and feldspar.
In the zone of contact metainorphism, garnet, epidote, calcite,
chalcopyrite, pyrite, and th(! remainder of the magnetite are
constituents introduced by metasomatic replacement.

The feldspar is both twinned and untwinned and is usually

quite * irbid from nltoratinn p-'wliirtw. In composition, it
Tungvs from orthodaso to aii.l iMl-aiiuritc. In the porpliyritic
typoM, the phrnocrystH occur in tiilMilur, hith.xhapcl, aiid Miuuro
form«,thcnv ^col the larncr ones hcinRiihout 1 •'> hy ()r)nim.
in »\zo. In tne uran^toid types the fonn is UMialiy poor am"
irreifiilar. Tiie plaKJoclasc is occasionally twinned according
to tlie all.ite law and a few individuals have the neUlitionrJ
rarlsl)ad t winnins;. Zonal structure is (,f rather rare ocf urnncc.
The ijlaniodase phenocrysts are often surrounded hy a thin
crust of clear untwiniicd feldspar with a crenulate outf-r hordrr.
Strain shadowswith incipient «ranidation are coiunioii. Chlorite
and iinionite traverse many of the individuals alnuk fracture
an(; cleavaKC planes. The mineral alters to kai>lin, turl.id
acurcKales of epidote, and carhonat. .- with (piart/. The horn-
blende is pale green and yellowish srecn and occurs in good
forms ill prismatic and basal sections, i.n av.Tane of the larj:er
individual being 1 by O-A mm. in size. It more often is found
in irrcKular individuals with frayed terminals. It is rarely
fresh and has either been leached to paler lints or altere<l to
chlorite with a separation of maKiietite. Many individuals
are completely altered to anjsrepate.^ of chlorite, epidote, and
calcite. The ijuartz 1-= clear and occurs in rounded individuals
up to 0-.") mm. in diameter. Outsiile of the uroundmass it is
in trilliuK amount. Apatite in dear colourless crystals and
acicularforui.uccurstis inclusions in dii't'i'ldsiiarand hornblende.
Magnetite occurs as primary grains included in the liornl)lendc,
as dust-liko particles with chlorite resulting fn.m the breaking
down of the hornbhnde, and as an ore mineral introduced at a
later period with the lime silicates. It forms rounded grains
and crystal aggregates up to 0-(i nun. in (Hameter. Epidote
associated occasionally with zoisite replaces hornblende and
feldspar along their cleavage planes in portions of the intrusive
adjacent to the mineral zone. Pyrite in grains and streaks
apparently replaces the horid)lende in part. It also occurs
distributed through the groundmass. Many of the grains are
Rurroimded by a rim of limonite. Calcite is usually .s.-^ociated
with the epidote but is al-o found in the groundmass in
irregular sponge-like individuals and interstitial grains. In
sheared portions of the rock adjacent to the ore bodies, irregular

planes are filled with epidote, zoisite, garnet, calcite, magnetite,
pyrite, and chalcopyrite.

The groundmass varies in relative amount in the different
types. In some types representing border facios it is micrcgranitic
in texture and consists essentially of orthoelasc, plagioclase,
and quartz. The feldspar occurs in tiny laths and grains up
to 0-0.3 ram. in diameter with smooth or interlocking borders,
with the quartz intorstitially developed. In addition, small
individuals of hornblende or its altered equivalent chlorite,
in platy and fibrous aggregates, grains of epidote, calcite'
magnetite, and pyrite are also present in small and varying
amounts.

HORNBLENDE PORPHYRITE.

The hornblende porphyrite occurs in thin dyke-like masses
intrufive in the rocks of the Knob Hill group. The rock is
dark grey, essentially porphyritic in texture with phenocrystsof
grey feldspar and black hornblende up to • 3 of an inch in length
embedded in a dense crystalline groundmass or base. The rock
weathers to a light brownish grey colour and has a rough pitted
surface. The feldspar is mainly twinned— a few sections show-
ing no twinning— and is basic oligoclase and andesine. It
occurs as well formed phenocrysts and tabular forms, the latter
showing the re-entrant angles of the albite twinning. It is
usually very turbid from alteration products, or epidote and
carbonates and numerous minute inclusions of pale green chlor-
ite. Brownish green hornblende as phenocrysts is in greater
amount than the feldspar and occurs in rounded idiomorphic
forms and irregular individuals up to 2 by 0-5 mm. in size. It
occasionally is intergrown with pale brown biotite. Some indi-
viduals have completely altered to chlorite and magnetite,
with or without epidote and zoisite, others are partly altered
and appear with irregular rims of turbid chlorite. The basr
consists of minute laths and grains of plagioclase, shreds and
plates of clilorite, secondary quartz in small aggregates of grains
along with a small amount of magnetite and pyrite. Some irre-
gular areas are filled with sheaf-like aggregates of actiuolite.

TERTIARY.

/rr -.(i^ Rocks.

l.NVP.ODUCriON.

The early Tertiary ( ' ( m ■>) ws a period of vigorous erosion
and the mountain systems resuitmk from folding and uplifts
during the later Mesozoic were reduced from the lofty alpine
type to mature forms, the peaks and ridges having a broadly
uniform elevation. The district is not regarded as having
reached the final stage of a peneplain, but was merely reduced
to moderate altitudes.'

In Oligocene time the broader valleys wholly or in part became
lake basins in which a series of sands, gravels, and clays were
deposited, becoming by induration sandstones, conglomerates,
and shales. In certain localities vegetation was sufficiently
luxurious to cause the formation of lignitic shales with some
beds of lignite coal. The forn\ation has been called the Kettle
River formation and from the efTccts of later erosion now appears
in isolated or detached areas throughout the district.

The Miocene and possibly the later Oligocene was a period of
wide-spread volcanic activity, during which time the district was
covered by a series of lava flows aggregating a great thickness.
The lavas consist of basalts, andesites, trachytes, and possibly
more acid types. The oldest lavas are basalt and the youngest
of the series is apparently an alkaline trachyte. They are known
as the Midway Volcanic group, and are unconformable to the
Kettle River formation. The unconformability indicates only
a comparatively short period of erosion. The lavas are cut by
their intrusive equivalents, olivine basalt, augite porphyrite,
monzonite, and pulaskite porphyry, which occur as dykes, sills,
and stocks. The period of lava flows was accompanied with

'Brock, R. W., Sum. Rep., Gm\. Surv., Can., 1902, pp. 93-94 A. Daly, R. A
The .\ccor(iance of Summit levels among Alpine Mountains." Jour, of Geo!., vol'
XIII, pp. 105-125.

and followed by earth movements, which produced warping and
faultmg particularly apparent along the contacts of the lavas
of the Midway Volcanic group and sediments of the Kettle River
formation.

The Midway Volcanic group is probably of the same age as the
Volcanic group of Dawson occurring in the Kamloops area
while the Kettle River formation corresponds to the Coldwater
group.

In the map-area no lavas are found though they occur in great
development immediately to the west (Fig. 2, p. 21) The
intru.sive equivalents, however, are well represented in dykes or
sills of olivine basalt, augitc porphyrite, monzonite porphyry and
pulaskite porphyry. In only one instance are they found cutting
one another, the case being a sill of monzonite porphyry cut by
a dyke of pulaskite porphyry (See general map).

The several types are porphyritic and show well marked
selvages or chilled borders an inch or so in width. The dykes are
found generally throughout the underground workings, but do
not increase in number with depth so quicklv here as elsewhere
in the Boundary. The augite porphyrite was not noted as out-
cropping at the surface, but two dykes, however, occur under-
ground, one in the Mother Lode mine, and one in the Crown Sil-
ver tunnel. Later movement al.^ng the dyke fissures has pro-
duced minor faulting with brcciiation.

LITIIOLOGY.

Olmne Basnlt-This rock occurs in only one dyke having a
length of 510 feet and a maximum width of 30 feet. It is a dark
grey, almost black porphyritic rock in which laths of grev plagio-
clase feldspar, phenocrysts of black pyroxene, and Vounded
individuals of yellowish green olivine are eml^cdded in a dense
fine grained base having the appearance of pitehstone. The
rock weathers to a rusty grey with a pitted surface due to the
removal of pyroxene and olivine individuals. Under the micro-
scope^the rock is seen to be comparatively fresh and consists of

labradorite, : igitc, olivine apatite, and magnetite. Thelabra-
dorite occurs in tabular, lath-shaped, and square individuals
up to 3 mm. in length. They have no uniform orientation
that would suggest fluidal structure but lie in all directions.
Many show the stop-like outline indicating incomplete growth.
Twinning is by the albitc law with occasionally the additional
Carlsbad twinning. Many of the individuals have symmetri-
cally arranged inclusions of the groundmass.

The augitc is pale yellow or colourless. The large individuals
are idiomorphic with sharp or rounded angles, and range in size
up to 1 • 3 by • G mm. Some have irregular borders with enibay-
ments indicating corrosion, and a tew are twinned polysyntheti-
cally. The mineral is fresh with Init slight alteration to chlorite
along cleavage and fracture jjlanes. It holds as inclusions a
few grains of almost completely serpentinized olivine.

The fresh olivine is colourless and occurs in rounded, irregular,
and wedge-shaped individuals up to 3 mm. in diameter. The
alteration to yellowish green serpentine follows the borders of
the individuals and the numerous irregular cracks traversing
them, with the fibres and plates of serpentine lying parallel
to the cracks which they traverse. Many of the smaller grains
are completely altered.

The groundmass is in relatively larger amount than the
' ts of irregular individuals and minute
of augite, fibres and plates of chlorite,
, rains and crystals. Colourless apatite
in slender crystals and roimded grains occurs as inclusions
in the augit(>, olivine, and feldspar.

phenocrysts and
laths of plagiocla
and a little magne

^ ;.(/i7c Porphijrile. — This type was on'y noted in two instances
and then as dykes in the undcrgrourd workings of the Mother
Lode and CrowTi Prince. The cb Ke in the Mother Lode mine
follows for a distance the fault plane or contact between the ore
body and the siliceous rocks of the Knob Hill group.

The rock is much c' iposed and rather soft from shearing
movements subsequent to its intrusion. It is dark grey in colour
and consists of phenocrysts of black pyroxene in a finer grained
mass of greenish grey feldspar, and minute black plates of
biotite. The rock is lamprophyric in its general texture.

Microscopically the feldspar is seen to be both twinned and
untwmned, but the alteration has been too great to permit
of any satisfactory determination of its composition. The
similar rock at Phoenix contained both orthoclase and acid
labradorite. Many of the turbid laths contain a large amount
of green ch.orite which has a certain symmetry in arrangement.
The augite is pale yellow and sl^ows good forms in basal and
prismatic sections. The size of the individuals ranges up to
1 mm. m diameter. It is less abundant than the feldspar but
occurs in mdividuals of larger size. It is but slightly altered,
chlorite being the secondary product. Biotite occurs in oblong
forms and irregular plates of which many are allotriomorphic
towards the feldspar. Magnetite in crystals and grains is in
considerable amount, and is found in contact with individuals
of augite and biotite or as inclusions in them. It al.o occurs in
dust-like grams and aggregates in chlorite. The groundmass
consists of laths of plagioclase, biotite, and pale green chlorite,
the latter occupying angular interspaces between feldspars
and being probably derived from the biotite.

The rock is closely related to the augite porphyrite occurring
at Phoenix, but is apparently more basic in character. An
analysis of the Phoenix rock by Mr. M. F. Connor of the Mines
Branch, is given below. According to the quantitative classifica-
tion the porphyrite is shoshonose.

^^^■' 55-90

^'^^ 15-.'S2

FejO, ,22

FeO ..22

M«?o ;:::::::;;;;;; 4.70

S'^^^ 5.79

N'^A^ 2-89

K2O 4.. 4c

It^ '■'■■-'--- 1-40

S 0-14

St, 0-46

^^^ 009

99. 3G

-:
a

Momonite Porphyrij .—In hand specimens this rock is grey
or greenish grey in colour and of porphyritic texture, with rosettes
or irregular clusters of light grey feldspar, in a highly feldspathic
trachytic or microgranitic groundmass in which minute laths of
glassy feldspar may be discerned. The rock weathers to a pale
rusty brown or dirty dull grey with a pitted surface, due to the
removal of many of the phenocrysts of feldspar and the grp'ns
of the dark (f.-rric) constituent. The rock occurs as dykes and
sills which present well marked chilled zones along their margins
Microscopically the rock consists of soda orthodase and
ohgoclase (Al„ A;, Al^V;), feldspar, augite, biotite, quartz,
calcite, chlorite, apatite, and magnetite. The phenocrysts of
soda orthodase are rounded, oblong, or square, in forms up to
2 -To by 1-.5 mm., and are occasionally twinned according to
the Carlsbad law. They are very turbid and arc usually sur-
rounded by a narrow zone (al)out 0- 1 mm. wide) of clear feldspar
in optical continuity with the main individual. The oligoclase
occurs in clusters of tabular and lath-like in.lividuals, the average
size of which IS smaller than those of soda orthodase (up to
0-7 X 0-3 mm.;. They are all twinned according to the albite
law and a few have the Carlsbad twinning. Thev are generally
turbid from kaolin and carbonates (calcite?) and are surro nded
by narrow zones of clear s„da orthodase. Strain shadows are
common in both fdds]iars.

Pale yellow augite occurs in rounded idiomorphic form- ip to
1-5 by 1 mm. in size. The mineral alters readily to chlorite
and the greater part has been altered to aggregates of chlorite
and calcite. Apatite and magn.'tite are in small amount- in
some slides the latter occurs in filiform aggregates, the minute
threads terminating in small lobes or possibly crystals. In
this form it is either included in the feldspar, or forms l)orders
about 0-1 mm. wide around phenocry.sts of soda orthodase, the
filaments being arranged with the longer axis at right angles
ti) th ■ margin of the phenocryst.

The groundmass is about three times the volume of the phen-
ocrysts and varies in texture. In some thin sections it consists of a
trachytic mass of laths and irregular grains of plagioclase • 3 by
00 mm, a little clear untwinned feldspar, minute oblong forms
(0-2 X 04 mm.) and plates of biotite allotriomorphic to the
3938—3

feldspar, and angular grains of clear quartz interstitial to the
feldspar, the latter at times in relatively large amount. Chlorite
and calcite are also present, the former being due to alteration
of biotite. This type passes to one in which there are fewer
laths of feldspar and more interlocking irregular grains, the tex-
ture becoming coarser and microgranitic. The rock is more
basic than the normal pulaskite and probably is closely related
to, if not identical with monzonite.

Pulaskite Porphyry.— The pulaskite porphyry (alkaline syenite
porphyry or bird's-eye porphyry) is closely reL.led to the above
described monzonite porphyry and is probably a slightly more
acid phaseof the same magma. It is acompact, greyish, porphy-
ritic rock consisting of phenocrysts of light grey feldspar with
greenish cast embedded in a dense felsiticor microgranitic ground-
mass which is highly feldspathic. The feldspars have a tendency
to arrange themselves in rosette-like clusters. The weathering
of the rock is characteristic, the border becoming a brownish
grey, while the phenocrysts become pale brown or pink.

Microscopically the texture of the rock is similar to the mon-
zonite porphyry, and the mineral content is also similar with
the exception that nearly all of the phenocrysts are soda
orthoclase, the few of plapioclase being acid oligoc]a>c. The
volume of the base is much greater than that of the phenocrysts.
The biotite which occurs intcrstitially to the feldspar in
the base, is in relatively small iimount and for the great par*
is altered to chlorite. The greater portion of the base consists
of soda orthoclase and oligoclase laths. Quartz occurs in very
small amount.

The analysis of the pulaskite porphyry occurring at Phoenix,
made by Mr. M. F. Connor of the Mines Branch, is given below
in column I,' and an analysis of the Rossland pulaskite by Dr.
Dittrich, Heidelberg, is placed in column II.'

The Phoenix rock according to the quantitative classification
is monzonose and it is probable that the pulaskite at Deadwood
belongs to the same type.

'LeRoy.O.E.
•Brock, R. W.,

Goologyand Ore Deposits of Phopnir. Memoir No. 21.
Sum. Rep., Geol. Surv., Can., 1902, p. 104 A.

S'02 57-3''

^1=^» 17-27

^'PaOs i.g2

t'e<-> 3..)4

^^'k^> 2-08

^'^^^ 4-24

Ni^sO 4..^

|J=^ 5.%

.^.='^- 0-08

''^*2 0-88

^f^ CM

•^^"•J 0-09

^'^ O-OG

liii<J 0-24

II.

• ")«

•23

•51

•02

',»<)

tr.

9!»-88 99^83
QUATERNARY.

covered by tlio C orchllerun ice .heet, the effects of which are
...nvn an the gl.Hatecl peaks and ridge, and in the nundl r o
errata.., some being blocks of great size. The general direction
of movement varied from S. 15^ W. to S. 41° E. mo.lified locally
by the mam topographic features during the closing period of

til' IC C tl^C,

In the map area the local directions of ice movement varied
f om ^ S.^^^ . to 8. G5= W. Weathering has to a great ext nt
obliterated the glacial striae on many of the rock surL-es thou^
the more siliceou.s rocks and the outcrops of magnetite have
retained very .listmct markings. Modified ,!rift in the form of
clays, sands, and gravels vvith w.-U rounded boulders occurs as
a mantle of varying thickness though usually thin, overlvinc
more t .an one-half of the area. In the <leepci valley^su i a!
that of Deadwood creek, the thickness is much greater and the
gravels and sandy clays are rudely stratified. No typical boulder
clay was seen.

'Brock, R. W., Sum. Kep., Oeol. Surv., Can d 96 A

3938— 3i ■ ■

CHAPTER IV.
ECONOMIC GEOLOGY.

DEADWOOD MINERAL ZONE.

INTRODUCTION.

The deposits of low grado copper ore of the Mother Lode
.T,nd .idjacent mines, Ofeur in a mineralized area — termed the
Deadwood mineral zone — whieh is a zone of eontact metamor-
pliism in the limestone of the Hrooklyn formation, characterized
chiefly by the development of lime silicates. The zone consists
essenti.illy of actinolite, garnet, epidote, calcite, and quartz,
in which the met-allic minerals chalcopyrite, pyrite, and magne-
tite have been deposited in certain favourable areas, so concen-
trated as to form irrej^ular ore bodies of considerable size. The
ganRue rock i.- tough, compact, and usuallj^ dark green from the
prevalence of actinolite. Where garnet and epidote predomi-
nate, the rock is harder, denser, and yellowish green or
])ale brown in colour. The rock is generally massive, but also
occurs roughly banded from alternating layers of the several
gangue minerals. It weathers to a reddish brown from the
dccompo-ition of the pyrite, with a surface usually deeply pitted
from the dissolving out of the nimierous small and irregular
ma-<ses of calcite, leaving garnet, epidote, and quartz standing in
relief (Plate III B). The ore bodies originallj' had a heavy
'iron hat' overlying their outcrop, that of the Mother Lode
being a p.irticularly noticeable feature in early prospecting
days.

DISTRIBUTION.

The mineralized zone, probably once continuous over a very
considerable area, has been sep.irated by erosion into a number
of isolated exposures, the major areas being those of the Mothei
Lode and Sunset, and the minor ones being the St. Lawrence,
lireat Hopes, and Marguerite.

I'lMl. IV.

A. Glory hole (in part) Mother Lode mine, 1910.

B. Quartz veinlets of three generations traversing a partially i-ilicified tuff (X 40 dia.)

otfoo — p. 32

The Mother Lode zone in roughly elliptical with a northerly
trend. It has a length of l/ino f,.,.t and a maximum width of
1,080 feet. The thickness varies from a foot or so to atxmt
550 feet. The vertical range from the highest point on the
outcrop to the lowest point in the underground workings, is
not less than 700 f.-et. The greiitest thickness is along the
northwest border and thins out towards the southeast (Oeiural
map-section A-B). The Sunset zone is also of elliptical form
on horizontal plan with a n()rthwe^t trend. It has a length of
550 feet, a maximum width of 3;{() feet, and a maximum
thickness of rather less than 50 feet.

GEOLOGICAL RELATIONS.

The Mother Lode zone lies in an irregular asymmetrical trough .
the northwest wall of wliicli is practically vertical and consists
of crystalline limestone. The main floor of the z..n(> is compos.d
of the siliceous rocks of tiu. Knol. Hill (rroup .-.nd granodiorite.
The contact between tiie liinc-toiie and Knol) Hill rocks is
apparently due to Mock faulting rather than to a sharp folding,
possibly a doui)le faulting', one approximately aldiig the strike
of the ore body and a second across it as shown by the marked
slip or crush zone from the 200 to the 40(» levels in the Mother
Lode mine. By this faulting the limestone was lowered into
the jasperoids, etc., of the Km)l. Hill group. Small lenses of
limestone also appear at a couple of points well within the mineral
zone. The zone is cut by Luter (T. rtiarv) dykes of augite
porphyrite, monzoniti>, and pulaskite porphyry which are
usually very irregular in size, strike, au<l attitude.
^ The Sunset zone lies on a Hoor of the jasperoids, etc., of the
Knob Hill group, and is roughly horizontal with' possibly a
slight tilt to the south. No limestone appears at any point in
or along this zone which is blanket-like in nature and shallow.
Dykes of pulaskite pori)hyry are relatively more numerous than
in the Mother Lode zone.

The Marguerite zone is not exposed and is probably covered
by a portion of the dump at the shaft. It must have a very
small surface outcrop and probably stands almost vertical.

The St. I.nwrrnco zone liox nlong the junction of the Brocklyn
fortniition and thr Knoh Kill Kroup. It ha:- !i l.-riRfli of nboiit
IW ii'tt jinil an rxpor<((l width of 10 fcrt. The Cnnt Ui>\w*
zonf is only a oronil patch, proJmt.ly not more than a fiw fret
thick at ttic dcopcst point, lyinj? on the hiliccoun rocks of tht'
Knob Hill group.

CHARACTEK OF TIIK ORi: DODIKS.

The ore hodicH arc irrcgiihir, h'ns-likf masses and vary widely
in si/e .'iiid attitude, the latter dependinR piohaMy on the thick-
ness and attitude of the original limestone. The ore hody
of the Mother Lode stands almost vertical along the fault
f.ace of the linie-t(.ne Mock where the vertical thickness
of the mineral zont -^ proh.al ly the greatest. The Sun-et ore
liodies .MTi' pra'tieally horizontal.

The foot-wall is either limestone or the .siliceous rocks of the
Knol. Hill Rroup, and is practically the commercial as well as
Ihe structural foot, though in jdaces a hand of barren gnngue
rock intervenes between the structural foot-wall and tlie ore
l)ody proper. The lianging-wall is visually a commercial one,
and the ore either insensibly becomes lower in grade, or the
p:iy ore suildeulv terminates ahjng a gouge fdled fissure or
••slip."

The ore bodies are traversed by a series of fissures, locally
termed "slips." These run in all directicms and at all attitudes
from vertical to horizontal. They vary 'n length from a few
feel to a hundred or more fi'et, and in width from :i fraction of
;!ii iiicli to several inc hes. The smaller ones pass by gradual
transitions into those of almost microscopic dimensions, ;u\d the
whole form a reticulating system of a very intricate nature and
of several ages. Faulting has been general, though u-ually with
sni:dl displacements. The system is .Mnalogoii- to that described
under jasp'Toids, and illustrated in Plate IV 15.

The fissures, no doubt, have generally I)een caused by stresses
set up during the process whereby tht limestone was being re-
placed by the lime silicates. They nr,- also considered as being
a most important factor in ore deposition, forming, as they did,
the channels of circulation for ore-beariug solutions, which

3:>

uradually passed from the trunk rlmnnds to the fim-r s.ries of
(li->ttilnitnri('f, thus iHTiuitlinR ani'vcn imd widf-sprciil (icposi-
tion of thfir mctiiilic ..,iit<iit. Muiiy of the fissuri's, citlitr
wholly or in part, were lill.tl withRouKc, and us impervious Imud^
wiTf thus importitiit in nuiding and dflicctinK the Kcmiiil
firciiiation, thi-rcliy pnmiotinK a better concentration of the
ore. In the closii\K perio<i many of these fissures were hlicd
with cah'ite and (pmrtz (the lii^t mincraN reniainiiiR in sohitioni
associated in places with >niiill amoun of chalcipyrite and
pyrite. SIIkIu movcment-i uIour these pn-niineral fissures have
taken place suh-ecpii'iit to thi' formation of the ore bodies, a^
evidenced by the many >lickcnsided >urfac(i.

\Vrd({c-.,liiiped massc-^ or ribs of almost birren Kancue rock
appear in all the ore b idles, and are usually obstat les to economic
mining. DependinR on their im()ortan( ,- and po~iti(m, they are
either stopcd or left standing. Tin' ore is so unifoiin in its h.w
grade character that much admixture of barren gangue would
quickly bring it below the shipping grade.

CHARACTER OF THi; ORE.

The ore is massive, rarely ban(UMl, and consists of chalcopyrite.
fjyrite, and magnetite, which are hnely and uniformly distributed
through the gangue minerals along fracture and cleavage j)lanes,
and interstitially between individual grains. The gangue min-
erals are actiiuilite, garnet (andradite), ei)idote, tremolite (rare),
zoisite (rare), chlorite, calcilr, mui (juartz. The ch.ilcopyrite
and pyrite are more closely associated with the (luartz and
calcite which fill fraclur( ^ and interstitial spaces in and between
the lime silicate minerals

Occasionally masses of chalcopyrite are found, but these arr
of relatively rare occurr'nce. Magnetite also occurs in irregular
leus-like masses, both along the bonier of the main ore botlios
and also .it various horizons through them. Azurite and
malachite were found in the surface zone of oxidation. Arsen-
opyrite, galena, zinc blende, and jiyrrhotite' have been noted
in very small quantities. The average ore ranges from 1-1 to
1-3 per cent of copper, and the gold and silver values amount
to about $1 per ton.

'Br-..-k, 11, W , ,s:ui,i, Rf^port, G-^j!. Su.-v-., C::n.. iooe, p. 11J.\.

The character of the ore differs mineralogically only from
that at Phoenix. At Phoenix, epidoteand garnet are predominant
and actinolite of rare occurrence. The iron oxide generally
distributed through the ore at Phoenix is hematite, the magne-
tite there occurring only in distinct masses.

Mineralogy .

Only the minerals composing the mineralized zone and ore
bodies will be considered under this heading. Arsonopyrite,
galena, blende, and pyrrhotite referred to in earlier reports' of
the area, were not noted by the writer.

Metallic Minerals.

Chnlcopyrite (sulphide of copper and iron)— Chalcopyrite is
the most important and valuable of the metallic minerals and
contains all the copper values, and practically all of the gold
and silver as well. It occurs as solitary grains and aggregates
up to 2-5 mm. in diameter, as narrow threads and streaks,
and as minute elongated lenses up to 12 mm. in length,
developed along cleavage, fracture, and shear planes in the
gangue minerals (Plate V, B). It is also found associated
with the calcite i^nd quartz which fill irregular areas in the u-
tinolite, and actinohte-garnet types of gangue, and usually
forms along the contact of the calcite or quartz with the lime
silicates. It is usually associated with iron pyrite, which, in
part, is contemporaneous with the chalcopyrite. It also sur-
rounds grains and well formed crystals of magnetite, as well as
filling minute fractures which traverse the latter mineral. It
is also found in larger masses which are relatively pure, but
these are of somewhat rare occurrence.

Iron Pyrite (disulphide of iron) — Iron pyrite is closely
associated with the chalcopyrite. It often occurs in gooa
crystal forms, the cube and pyritohedron being the more
common, and combinations of the cube and octahedron

'Brock, K. W., Sum. Report, Geol. Surv., Can., 1902, p. 1I9A.

Pmtk V.

A. Clarnct crystals in ralcite (40 diamotors).

B. Chalcopyrite (blatk mineral) in actinolite (grey minoral) (40 diameter*)
3938— p. 36

being less so. The crystals vary in size up to a quarter
of an inch in diameter. Microscopically they are found
disseminated through the gangue minerals in sizes up to 0-1
mm. in diameter. The mineral has a wider range in deposition
than the chalcopyrite, part of the pyrite being about the last
of the minerals to crystallize.

Magnetite (magnetic oxide of iron) — Magnetite occurs
generally distributed, in grains and crystals, both solitary
and in aggregates of octahedra, throughout the gangue
minerals and favouring the contact between the lime sili-
cates and the calcite or quartz. It also occurs as massive
bands alternating with actinolite and garnet and as large irregu-
lar lens-like masses of varying size at different horizons in the
ore bodies.

It has been formed earlier than the sulphides and is in part
slightly later, and in part contemporaneous with the lime sili-
cates. When massive the magnetite forms a dense crystalline
aggregate, in which the sulphides are irregularly disseminated,
occupying interstitial spaces between the grains, or filling minute
zones of shear and brecciation. It is usually traversed by
numerous seams of quartz and calcite. Narrow brecciatcd
zones were noted, with the fragments of magnetite cemented
with quartz or calcite.

Limonite (hydrous sesquioxidc of iron)— Limonite, in brown
and reddish tones, results from the decomposition of the
sulphides. It often forms a coating on pyrite, and on chal-
copyrite with malachite. It occurs generally throughout
the ore bodies as thin films along joint and shear planes, and
fills microscopic cracks in the garnet (Plate V, A) and cleavage
planes in the actinolite.

Malachite (green hydrous carbonate of copper) — Malachite
of pale green colour and rather dull lustre occurs as botryoidal
incrustations on chalcopyrite. Azurite probably occurs also
but was not noted. The oxidized zone has in great part
been mined, hence but relatively little of the secondary metallic
minerals are now to be seen.

38
Non-Metallic Minerals.

Actinolite (magnesium-calcium-iron-amphibole)— Actinolitc is
the best developed and most widely distributed gangue
mineral. It varies from pale green to greenish grey and is
pleochroic in pale green, almost colourless and yellowish green
tones. In places it occurs in columnar masses with fibres several
inches in length, which show the eminent cleavage and the char-
acteristic basal parting. It generally occurs in acicular and lath
forms with frayed or ragged terminals, arranged either without
any particular orientation, or in sheaf-like and radiate clusters
forming felty masses which in the aggregate produce a gangue
of considerable toughness. At times it appears intergrown with
magnetite. The sulphides are deposited in it along the planes of
cleavage and parting (Photo B, Plate V) and in minute shear
planes. A black variety of hornblende associated with pyrite
and calcite occurs in veins filling fissures in the massive actinolite.
Along some of the larger shear zones the actinolite has been
converted into a substance resembling "mountain leatlier"
consisting of series of interlacing flat thin leaves and fibres, pale
grey in colour but lacking the quality of toughness.

Tremolite (lime-magnesia silicate)— Tremolite was only noted
microscopically and is of rare occurrence. It is colourless
and forms sheaf-like aggregates associated with other gangue
minerals.

Garnet (andradite-lime Iron silicate)— Garnet occurs both
massive and in crystals. A test analysis by M. F. Connor of
the Mines Branch, showed distinctly that the variety was
andradite. The colour is reddish brown, pale brown, and
honey yellow with usually a resinous lustre. The crystals
present the rhombic dodecahedron and combinations of it
with the tetragonal trisoctahedron, and have formed freely
towards or along the borders of the calcite filled areas (Photo A
Plate V). Microscopically the massive garnet is pale yell v
and occurs in aggregates of rounded polygonal forms traversed
by numerous cracks. In all the slides examined it was seen to be
quite isotropic. The crystals vary up to 2 mm. in diameter and

have developed freely towards the calcite and quartz. The
massive garnet has been finely breeciated locally by later move-
ments, and the angular fragments are cemented together by
quartz or calcite. In some instances the brecciation has pro-
duced a finely comminut<d microscopic dust cemented by calcite
•n which minute grains of ore have been deposited. To a very
slight extent the garnet has suffered alteration to chlorite along
minute shear or fracture planes.

Epidote (lime-iron-aluminium silicate)— Epidote is present in
relatively small amount and is usually found in the mixed
gangue of actinolitc and garnet. On fresh fracture it is bright
green or yellowish green but weathers dull or earthy. Crystals
are not common and its usual occurrence is in small granular
masses. \\ here sheared it assumes a finely fibrous aggregate
It rr-r'aces the feldspar and fcmic minerals in the granodiorite
and m certain instances is found replacing limestone in narrow
parallel bands alternating with quartz and calcite (Photo B
Plate III).

Zoisite (lime epidote)-Zoisitc was only noted microscopi-
cally. It IS colourless, and occuio in minute crystals and grains
associated with epidote.

CA/on7e— Chlorite is not abundant. It is pale green, and
occurs to a very limited extent as an alteration product of
garnet, and to a greater extent from the breaking down of the
actinolite along lines of shear.

Calcite (carbonate of calcium.)— Calcite varies from dark
grey to pure white, and occurs in irregular areas in the lime
silicates, as veinlots traversing them, and as the cement in
jnes of brecciation. It is usually associated with quartz and
also with the sulphide minerals. It has been known to occur
in a very pure state, and some excellent crystals of Iceland spar
have been found in the Mother Lode mine. At various horizons
m the Mother Lode mine the calcite forms the bulk of the
gangue to the exclusion of the lime silicates.

Quartz (oxide of silicon)— Quartz is light grey and usually
occurs in a manner similar to that described under calcite. It
does not, however, form large masses in the gangue but is found
as grains and einlets associated with calcite.

ORIGIN OF THE ORE BODIES.

The copper-gold-silver deposits of the Mother Lode and
adjacent mines occcur in a zone of contact metamorphism
characterized chiefly in its mineral composition by the abund-
ant development of actinolite, garnet, and epidote. The zone,
however, is susceptible of two divisions, one being composed
almost entirely of crystalline limestone, the other being made
up of lime-silicates chiefly and the ore minerals (See general
map). The direct cause of these contact zones is believed to be
the intrusion or intrusions of the granodiorite of Jurassic(?)
age, which have either invaded limestone formations, or have
been intruded sufficiently close to such formations as to pro-
foundly alter them. The granodiorite is also considered as the
source of the metallic minerals forming the ore. While the
evidence generally through the Boundary district is not abso-
lutely conclusive there is apparently an absence of any other
geological factor of sufficient importance to be accounted the
prime agent.

In the replacement of the limestone, actinolite, garnet, and
epidote were the first to form, and a great part of the magnetite
was practically contemporaneous with them. At a slightly
later period, the character of the mineralizing vapours or solutions
changed somewhat, with the consequent introduction of chal-
copyrite and pyrite, which were deposited in fissures, minute
cracks, cleavage planes, and interstitial cavities. The final
phase of deposition is represented by quartz and calcite which
filled all remaining cavities and spaces.

From the prevalence of chalcopyrite, Weed in his genetic
classification of ore deposits has referred these to the Cananea
type of contact metamorphic deposits."

In the ]Mother Lode mine the granodiorite forms a part of the
east wall of the ore body; it also underlies the ore bearing zones
of the Crown Silver, Marguerite, and the Sunset in part. At
other points in the Boundary district as well as in this area
the granodiorite has been found, locally, to have been replaced
byjime silicates, along with ore bearing sulphides. In such

Ene.', *V d'brms, %'Flir^!' "*" '"'^''^ ^°"'-"-

Trans. Amer. Inst. Min.

cases it seems possible, that, with a differential cooling in the
batholith, certain portions of the border have solidified in
contact with limestone, and both rocks have been subsequently
attacked by vapours or solutions from the sti" fluid portions of
the magma, thus producing lime silicates in the rocks on both
sides of the contact.

With regard to the origin of the lime silicates there is a con-
siderable diversity of opinion, which may be classified under
two schools of thought.' On the one hand it is . ontended that
the results are brought about by the metamorphism of impure
limestone at, and adjacent to the contact of igneous intrusive
rocks, with little or no addition of material from the latter;
while the other school advances the view that foreign material
from igneous sources was to a greater or less extent introduced,
combining with and replacing the limestone, by various species
of lime silicates.

From the great diversity of contact deposits it seems probable
that one or the other school is correct in certain occurrences,
while in other cases a modification of the two would appear to be
the more correct hypothesis. In certain instances it has been
noted that pure limestone bands only were replaced, while in
other cases the reverse has been found true. Besides the charac-
ter of the replaced rock, the composition of the magma of the
intrusive rock is probably an important factor, as well as the
size and attitude of the mass.

The residual limestone in the vicinity of the Mother Lode
and Marguerite is now wholly crystalline, and is comparatively
pure containing but trifling amounts of silica, iron and alumina
(see analyses, chapter HI, page 19).

If these analyses approximately represent the composition
of the original rock, it is, therefore, necessary to assume that
the rock has received important adi'Hions or ferric iron, alumina,
and silica to account for the large volume of lime-iron and
lime-iron-alumina silicates and magnetite now present in the
contact zone. It also seems probable that the limestone origi-

,, . 'B:i"P'}.Jo3epli- Piiysic;il EfTects of Contact Metamorphism. Amer Jour of
Srience, V ol 13, l'J02, pp. 279-296 ;in(l literature ref.rred to in this piper

Kmiip J !• Ore Deposits at tlie foutacta of Intrusive Koeks and Limestones,
r.con. Oeol., vol. 2, 1907. pp. 1-13.

GeoPvof T'lOO? ^ ''"'lOS^l'i?''"* "' '^"^ Deposits to Physical Conditions. Econ.

nally was ratl.er pure, for the present erystallino types though
oecurrmKin hirge n.as.es over eonsiderable areas, give no indica-
tions in their average composition that the rock contained more
impurities than at present.

While a definite statement is hardly warranted it seems highly
probab o that the limestone has been r..placed by solutions
derived from igneous sources which carried ferric iron, alumina,
and silica, attacking and dissolving the limestone and forming
lime silicates with a liberation of carbonic acid gas and water

CHAPTER V.

DETAILED DESCRIPTIONS OF MINES.

TKE BRITISH COLUMBIA COPPER COMPANY
LIMITED.

INTRODUCTION.

The holdings of the British Columbia Copper Company at
Deadwood consist of six claims, namely, the Mother Lode,
Primrose, Offspring, Tenhrock, Don Julis, and Sunflower.
The Company also controls the Sunset group consisting of the
Sunset, Crown Silver, C.O.D., and Florence claims. The
former group, of which the Mother Lode is the chief, was bonded
for 814,000 in 1896 by Col. J. Weir of New York, who formed the
Boundary Mines Company which in 1898 became the British
Columbia Copper Company. The Sunset group was sold in
1897 to W. L. Hogg of Montreal. In 1899 the group was known
as the Montreal and Boundary Creek Mining Company. The
property was taken over in 1900 by the Montreal and Boston
Company whi'.'h purchased the smelter of the Standard Pyritic
Smelting Company situated at Boundary Falls. The Dominion
Copper Company formed in 1905 assumed control for 4 years,
and was then reorganized in 1909 under t)>e name of the New
Dominion Copper Company, in which the British Columbia
Copper Company has the controlling interest.

The principal mines operated by the British Columbia
Copper Company in 1910 were the Mother Lode at Deadwood,
the Oro Denoro at Summit, the Jackpot in Wellington camp,
and the Rawhide at Phoenix. The Lone Star and Napoleon
mines in the State of Washington are also being developed and
will shortly add very materially to the general ore production.
The ore from the Napoleon and Jackpot supplies the deficiency
f sulphur which exists in the normal low grade copper bodies,
ypical of the Boundary district.

hJhLr"'.*"^'!.?^ **"" '"'"P""^ " "'*"»**''' »t Anaconda and

Jr't Zr *1 ""^ *''"'' '° ^""'^^ "^ "'•--'^y demand*. The
arHt furnace wm blown m on February 18, 1901, and the second
one wa. .nstallcd in 1902. At pro.ont 'the smeltery conrts
o three furnnces wh.ch treu. from 1800 to 2400 tons per day
with a maximum capacity of 2G(H) tons. During the early yvlrs
the mate wa. .hipped direct, but in Vm a bJcu.. rLTng plan
was msta Ic^ to convert the matte to blister copper. The p r
consists of 2 converter stands with 7 horizontal shells and Is
a capacity of between 40 and .50 tons of matte in 24 hours. The

verted to bltster copper about 993 per cent pure and carrying
the gold and silver values. The blister copper is shipped to
New Jersey for complete refinement
at Bonlr T^Z n "'''* f ^"-""^hout. being derived from the plant

The enJ^ f* ' °" ""' ^"°*'^°'»y "^'^^ «°™'- «5 miles distant
The coke supply is procured from the International Coal a^d
Coke Company at Coleman, Alberta. About 120 men Tre
usually employed at the smeltery. The smeltery r .Boundary

u^uTlte^e^rm^Zr^--^^--'---^

MOTHER LODE MINE.
Location.

urZf ^"u*"? ^"'^f '"'"' '' ''*"^**^d °" *»>« ^'^^t Side of Dead-
wood creek at an elevation of 3450 feet above sea-level It is

spur of the Canadian Pacific railway about 3J miles long.

Production.

The mine is the second in importance in the Boundary dis-
trict and ranks next to the Knob Hill-lronsides mine at Phoent

t_o2^14,481 tons of ore smelted. The recovered values amount

20, imf^pVn.im^''''''''^ ^°'"»' «°"^«'« «""k., Eng. ^ tlin. Jour.. Mar
3938—4

to 37,648,2^'! I iinds of copper; 93,024-2 ounces of g.tld; and
336,S80a oiir.'t of wilver. The iiv< rngo value jM-r ton tliust
iimouhts to !>< ».s pounds of copper, 041 ounces of gold, and
0-167 ounces of ^ I. r.

/ ' lojmtnt and Equipment.

The mi
500 foot le
200 foot If i.^
Above the o'' f"
mine ia d« m'-.
hole" (PI. 1
fompartnur '
hoisting ore,
been eonstru

■d I.,

i ;'.ncl
out", '

I'd by a four conipiirtment I'haft to ilic
'U at 60, 200, :}(M), iiiid 400 f(>et ; t f • (iO ai„
) conne tt-d with the surfao by tunnels.
I to tl • tvTi ,.j,t p„int ,„j the outcrop, the
•' ■ ' . -irrics forminR a large "glory
' ' '■: niap). The shaft is a vertical 4
mpiirtments of whiiii are used f«r

ne for iiiM lud one manwuy. Ore pockets hav«
' fl Iw'' >^ • " ^^ -•!, and all ore won in the mine
is raised in -ton skips. tiorse haulage is used on the GO anil
200 foot levels, and electri liimlage on the 300 and 400. Thi
mine is ligh'id throughout by electricity. From the upper hins
!it the shaft jwcket head, the ore is dropped to Blak. crushers,
ind after crushing is carried on a belt conveyer to the shipping
bins which have a capacity of 2000 tons. These are situated
near the terminus of the spur lino, and the ore is hauled to the
smeltery in :>0 to 50 ton cars. Air is furnished by two compress-
ors, one Rand and one Ingersol-Sargent, with an aggregate
capacity of 70 drills. Electricity as motive power is used
throughout with the exception of the haulage on the 00 and 200
foot levels. About 235 men are employed at llie mine.

Methods of Mining.

Parallel drifts are run in the direction of the strike of the ore
body, one being at or near the foot-wall, and the series are
connected by cross-cuts. Raises with chutes are put up about
every 35 feet, commencing in or near ore and connectinp; with
one another at intervals, and also with the level immediately
above. The method of sloping is that of the (.illar and room.
The raises from the several levels were originally driven in spiral
forms, but recently the method has been changed to a straight

1!^ 1 ,T^%«"*""^ i^fi™ «nd requires little or no timhrinK
iH-j oncl the chut,^. while the number of pillar, left for «upp<,rH
dcj>end on the local eharaeter of the in.m.Hliate groun.f with
refcrenee to the attitude of the f.Hsure. or -.lipV' The ",r
ace ore is «till LeinR won from n nerie. of cuarries forming
the loTKc "glory hoi.." (Plate I a,.,! Plate IV A) The ore

driflZT "'"'" '? ""' *^" ""'^ 2(K) foot l..vel.. Diamond

dnilmg ha. m .. • past l.m. extensively us,d to do the initial
prospectmgand to outline the general dimensions of tl. ore

Geological Rilatiom and Character of the Or ';,„ y.

There is apparently but one or. bo.ly, though of irregular
form, when examine.l m detad. In . .rtain sections of the work-
mgH where two or more bodies wer. develop,.!, it was foun.i
by later work that they were eonneet, J with tl. main ore bodv
the separating masses being ribs or irregular wedges of low^r'
grade ore, or almost I rren gangue.

Along the outerop the ore bo.ly has a length of about 1,100
feet (see general m.,,). The length, however, diminishes with
M-pth and on the 4..0 foot level is a liMe less than 250 feet

... *, i", ^:^r ^'""^ '" '" ""' '^^ maximum, with an aver:

ag.' ot about 40 f..et. The thickness of ,)„. ore is m.nlified bv
the number of lean wedges or ribs which may occur nucrbanded
with It. As an example, a cross section at one point on the 60
fo<)t level gay.., starting at the foot-wall, ore !() feet, waste
40 ,. jet ore 30. wast,- 18 ore 82, waste 27, ore 5-u total of
107 feot of „r.- and 85 fe.-t of lean or barren gangu, The
general contmuity of the ore body is brok.-n by an upward
truncated cone-shap.-l mass (body) of lean and barn-n gangue
wuch extends from the base of the mineral ,.one ulmos- ro the
bO foot level. The vertical ran^e from the highest point on
the outcrop to the lowest dev.Iop.-d portion of the or,- bjdv
amounts to about C50 feet. '

The general strike is N. :in= E., with a ,.urv. to to ea^t ^t
the north end of th, ore bo.ly. Tlu- ,lip is to -h,. south.-^st
and vanes from 45° to 70», steepening with .lepth until the lowe;
half of the ore body is practically vertical Section A-p. gener-d
map.) ** '"i.n

393s— 4i

The foot-wall is crystalline limestone and the ore is cither
in close contact with it, or is separated by a narrow band of
the gangue minerals (section A-R, general map).

The contact of ore or gangue with the limestone ia usually
quite sharp, and the limestone wall often presents an irregular
angular or broken surface without a distinct foot-wall fissure.
The hanging or east wall is, on the whole, a commercial one
and consists of the usual gangue minerals, or partly epidotizcd
ancl mineralized granodiorite. Along the south boundary,
which is marked by a fault from the 200 to 400 foot levels, the
ore body is in contact with the rocks of the Knob Hill group.

The system of fissurcis, of several ages, which traverse the ore
body in all directions and at all attitudes, has been an important
factor in the distribution of the ore. Along the borders of
some the ore is noticeably of slightly higher grade than the aver-
age, but gradually fades out into normal ore. Subsequent to
its formation, the ore body has been cut by dykes of pulaskitc
porphyry. They vary from a few inches to over 20 feet in
thickness, and are found at all levels from the surface to the
500 foot level. A main dyke on the 200 foot level extends along
the length of the ore body and dips into the foot-wall. On
account of its low dip it has been a serious obstacle in mining.
The ore along the borders of these dykes is of higher grade than
the average. This may be a concentration, due to a mineral-
izing action set up by the intrusion, or the dykes may have
followed some of the more important prc-mineral fissures,
which have higher grade ore along these walls, as noted above!
One dyke of augite porphyrite occurs at the north end of the
ore body along the contact between ore and country rock on
the levels following u fault fi.ssure. Later movements have
crushed and altered it to a great extent. The thickness varies
up to 25 feet and it dips south at about 55°.

Character of the Ore.

The ore consisi? of chalcopyrite, pyrite, and magnetite as
grains, aggregates, and thread-like streaks and lenses, sparsely,
though uniformly distributed through a gangue composed of
varying proportions of actinolite, garnet, epidote, calcite, and

quartz. Chalcopyritn also occurs in larRor and purer massos,
but these arc relatively rare. Magnetite occurs in irregular
mass..s and l.-nses of consi.l.rable size, ..,,,(1 often can bo mined
separately from the general ore: they are found both along
the bord.r and at various horizons in the ore body.

With the variation of gangue three types of ore can be differ-
entiated: a siliceous where the lime-silicates predominate, a
calcareous rich ni calcite, and a ferruginous composed largely
of magnetite. ^

Analyses of these types give the following results:—

f'ilica

Alunijnfi

Iron oiiili'

Liiiic iin^l iiiaf^ncHia.

yiliotiu.i (iilcaridui Fcrnntinous
27 -.i;!

44 23
7-4C.

IB 03

20 10

I'itl

12 00

34 00

SI 13
10 •26*

•British Columbia Mining H.conI, May 1902, p. 173.

Through the courtesy of the British Columbia Copper Com-
pany the writer is enabled to r»ublish the following analysis by
Mr. Frederic Kefftr, the consulting engineer of the Company.

AVEBAGE OBE OF THE MOTHER LODE MINE.

Alumina Allcalculatf<ia»conibln(fla(..ilicate ag.ig

Lime (CaO).......

10 in

Total 18-81 p<Tccnt . .fAncarlioniil<!., ....'. 8-34

\A8 Eilic'uli.' 047

Hagnriia.

Potaali .,

Sixla „

rarijonicoiidc (ciM .::::,::::::::::::::::: AHPHioiumcari^^^^^

J-opper Asclialropyritr

Total !•■.■ is 14 -38 ' . f In rlial(„,,y nil.' .. . ! .

iln pyritc I'VS,.

Iron.

2-fig

25
0-,'i2
7-34
l'U4

1 71

s-'ph" To..ii84.i3 |;J:!:,:r:;.y±-:::--; tH

218
3 OS
4S
(15

Oiygcn... (Aspyri(,-s .

^'"" Total Ml /A.. muJurr .;.

ICombiniKl water.

Total 100-25

The copper, gold, and silver values arc mainly in the chal-
copyrite. The average assays of the ore give !-l to 1-3 per
cent of copper, with $1 . 10 to $1 .20 in gold and silver.

THE SUNSET MINE.
Location.

The Sunset mine is situated southeast of the Mother Lodo
and about a fourth of a mile from it. The same spur of the
Canadian Pacific railway connecting the Mother Lode mine
connects the Sunset with the main line at Greenwood

Production.

From lack of data no authentic statement can be made re-
gardmg the production of the mine in the past. The mine

^r^A^ "°'°"^°f d ^^'PP^« i° 1901. but has been idle since
1908. It IS probable that the total amount of ore shipped in
the interval between these years is rather less than 100,000 tons.

Development and Equipment.

^Jit T^%'' developed by a series of open quarries, a tunnel
at the 100 foot level with a vertical two-cumpartment shaft
from that level to the 300 foot level. The shaft was filled with
water m 1910, and consequently the 200 and 300 foot levels
were not examined. In all over 5,000 feet (lineal) of develop-
ment work has been done.

T.,^1^ T I'''"'''''"' ''"' ''*"**^^ °° th*' «a"e spur line as the
Mother Lode and are connected by tracks to the quarries.

Geological Relations and Character of the Or. Bodies.

The ore bodies are irregular and comparatively thin, lying
approximately horizontal, and with rather indefinite boundaries
between the pay ore and lean gangue rock. They lie on a floor
of the siliceous rocks-cherts and jasperoids-of the Knob Hill

group (Section A-B-general map) and to a limited extent on
small masses of granodiorite. All the ore with the exception of
a body of magnetite near the portal of the tunnel, lies above the
100 foot level, the main stopes connecting with the easternmost
quarry. The west body has a surface area of about 24,000 square
feet with a variable thickness not exceeding 25 feet as the maxi-
mum. The east body has an area of about 12,000 feet and is
rarely more than 25 feet thick passing to a foot or so. Both ore
bodies are cut by dykes of pulaskite porphyry, and also show the
effects of later movements in sheared and slickensided zones.

Character of the Ore.

The ore is largely of the magnetite type associated as a rule
with a large amount of actinolite. The copper (chalcopyrite)
content is relatively low as an average. The ore is cut by numer-
ous small seams of calcite and quartz, and narrow brecciated
zones have been cemented with quartz. Lenses or masses of
chalcopyrite in garnet gangue were noted in the intermediate
stopes, but apparently are of small size, though containing a
greater amount of copper thpi the magnetite does. On the 300
loot level a vein was met with filling a fissure in the siliceous
rocAS of the Knob Hill group. The ore consisted of marcasite in
quartz and was stated to carry high gold values. It has not
been developed as yet.

THE CROWx>f SILVER MINE.

The Crown Silver mine lies to the east of the Mot' er Lode on
the eastern edge of the Mother Lode zone. The development
consists of a vertical shaft 250 feet deep with levels at 150 and
250 feet. A tunnrl 86 feet below the collar of the shaft was
driven in a westerly direction for about 300 feet, mostly in min-
eral zone.

No ore was encountered, the mineral zone carrying but trifling
amounts of chalcopyrite. From the material on the dump it is
evident that part of the lower shaft workings are in granodiorite

THE QUEBEC COPPER COMPANY, LIMITED.

THE MARGUERITE MINE.

The Marguerite mine is situated near the eastern border of
the map-area and is about 4000 feet ea^t nf fV,„ /t *u T ?
mine. It is owned by the Quebec Copp: CompanT The '
body or bodies have been developed by a sSli f t ^

100 foot level wh^e twi o e bodf" '""'"''"' °""""'^ *° ''''
22 feet thick respecthdy A^st ITZlT:^ ^^^"'^
good returns in copper, gold anS silver F .. "'' ^''"°
on the dump it is a^par'en^ tttron^d^iab/r^ wl^r fn
a barren mass of grancdiorite °

INDEX.

Actinolite f*"*-

Anaoondu, smelter at. .'.'.",.'. 38, 48, 51, 52

Analysis, auuife inrphyrito.. *• 45

I' limestones '." ' ' 28

Mother Lode ore ... 19

1^' Pii'nskitcporpliyry....'..^]. 49

Roiwlanu pulaskite 31

Bibliography

Boundary Falls, smeltery at dismantieHl
Mines Co.

-- „ 45

Boyd, W. H., topoiiraphioal work i)y 43

British Columbia Copper Co 3

., ", a'-knowled^ments. '' *?

rlaimsheldby «

Rropt R w ownersofMotlicrLode... ^

arockRW.,rcTOnnai89ance survey by *

Brooklyn formation * 5

Calcite

Chalcopyrite ''■'■'.'■'......'.

"^ Mareuerite mine. .... ......

^^ Mother Lode ore

. Sunset mine ore

Chlorite

Climate

C.O.D.elaim

Connor, M. F., analysis, auKiteporFhyrite... '..'.;.

„ " limestones '

f I'j .. I... ." Pulaskiiennrpbyrv.

uopper, Deadwooil mineral zone

_" '"rcelyprodured in Boundary district
low (trade. Brooklyn formation

MiirEuerilemine

" Mother Lodeore. ...'..'.
^^ produced at Mother Lode.

__ smeltery at Anaconda

Sunset mineore...
Crown Silver claim

;; ;; ." located.'.'.'.. ;;::::::;::;;:;;;;;

mine

39,

48, 52
3S
52
48
51
39
8
43
28
19
31
1
32
1
17
52
49
45
45
SI
43
4
51

Daly Dr. R. A., gcoloRical examination by.
Ucadwood mineral zone

^^ ""iinE camp, situation of...

n-i. ■ u ^ '"■'"'"'•< "in of mini sat

Uittrieh, Dr.. analysi.^ Rossland pulaskite

Dominion Copper Co wu^mhim;.

Don.Iulisclaim

Drysdale, C.W., .ireal iteolony by . '.'.'.'.'.'.,',

S
32

S
31
43
43

Ea«t, John, Sunset claim located by
CitniTia mine, copper producer
Epidote

Paoi.
4
1

.39, 48

Flora

Florence claim .

8
48

Garnet

Geoloty, economic.,..! !.......,'..'.' ' 38, 40, S2

" Kcncral 32

" Mother Lode mine '0

Sunaetmine 47

Gold, Boundary diatrict M

" discovery o( in Boundary creek •

discovery of in Rowland 3

^ Marguerite mine 8

' Mother Lode ore 82

" production of at Mother Lode *•

Sunset mineore 46

Gold Drop mine, copper producer... *•

G«at&o^"'^!.'i™'""«' Smelting, and PoWerCo-. ! ! ! . . ! {

Green wood, where 8i timted !........ !..^.''" 3*

Hogg, W. L., purchaser of Sunset group „

Iceland spar found in Mother Lode mine

Ingram, Wm., Crown Silver claim located by '?

Iron pynte ' 4

Irrigation necessary for agriculture "

Jackpot mine operated by B. C. Copper Co.

Jasperoids ft^' -^yi ^

Keffer, Frederic, analyses Mother Lode ore ,.

Kettle River formation... *»

Knob Hill group 28

Knob Hill-Ironsides mine, copper producer *?

Limestones, analyses of

Limonite

Lone Star mine

37
43

■

McCormick, Wtn.. Mother Lode located by ''*°*:

Magnetite ' 4

" Marguerite mine.... '^

" Mother I^core M

" Sunset mine ore ... *8

Malachite H

Marguerite mine, anal^aexot limestone. . ..^ ! ?I

' ' location, etc Jj

" lone M

Meaosoiu, detailed de.tcriptiun of.. S

Metallic minerals w

Midway volcanic group 3fl

Monarch mine, conpcrproducer 28, 29

Montreal and Boston Co. •

Montrealand Boundary Creek Mining Co!.' ^ J?

Mother Lode, analysisof limestotic. TJ

' " B.C. Copper Co., holders of....! J?

copper producer *f

' " equipment, etc •

history of *?

" located «

.'.' operated by B.C. Copper Co. i?

production of , "

" »one '-'■'■''■'■'■'■'■'■'■'■''■'■'''':^.':::::::::::::::::. ■ 33

Napoleon mine

New Dominion Copper Co. ..............'..'.'.'.',■■ . ™

Non-metallic minerals **

Offspringclaim

Ore bodies, origin of ™

Oro Denoro mine, copper producer ,

operatedby B.C. Copper Co.. '.'.'...'..'.'...■.■.■.■.'.■'. '.'■."'■■■'■■ 43

PaliMsoic. detailed description of... ,,

Primrose claim 'J

Pyrite, Marguerite mine ™

" Mother Lodeore ■.■..'.'.'.'.'.'..■.'.■.■.■.■.■.■.■.'.■.■.■.'.■. «

Quarts

Quaternary 39, 48, S2

Quebec Copper Co., owners Marguerite mine. . 52

B
Rawhide mine, copper producer

D '1 J "a- °pe™*<'d*)yB.c.copper Co.. !!;.:.:.:;. X

Kossland, discovery of gold-copper depositjj at 3

St. Lawrence rone

Silver, Boundary district '•

Silver, Miir urrlti- mine ^*''"-

" MiilliiT LinlO'iru , 88

" priKlui-tionutMuthori^ilo'.'. *•

Jjiowolioo mini , .-(ipiMT pr.i.lm-pr <•

»l indiirU I'vritic .smeltinir Co 1

Sunll. pwtT iliiim 43

Bunsi'i claim loiated <3

" itrouj) ."...',..., • *

" mini', production, etc.. *3

lone JO

Tenbr.-vck claim

Tertiar.v, 'Ictailol d'gcription r,( ♦>

Timi'e''r*'"' "'"'""''*• *'»"»ef Lode located by .'.■.■.■.■. '.'.'.'.'.'.'.'.'.['..'.'.'.'. ^

Toponraphy It

Tremolitc f7

W
War Eaffle mine, copner producer

Weir, John, bonded Motiier Lode mine. '

4, 43

Zoigitr

CLASSIFIED LIST OF RECENT REPORTS OF
GEOLOGICAL SURVEY.

Since 1910, reports issued by the Geological Survey have
been called memoirs and have been numbered Memoir 1,
Memoir 2, etc. Owing to delays incidental to the publishing
of reports and their accompanying maps, not all of the reports
have been called memoirs, and the memoirs have not been
issued in the order of their assigned numbers, and, therefore, the
following list has been prepared to prevent any misconceptions
arising on this account.

Memoirs and Reports Published During 1910.

REPORTS.

CoUina. No. 1058. "'P"K<m and Clay lake, Ont.— by W H

Cana'dr bVn' W.=Kl'i°«'^!;!o'7i}.'?'" '"'' "'"'""'t.riMic, „f ,he oil-hal.- depo.it. o(

MlUOIR 1.

Memoir 2.
MtMOIB 3.

HcMoiit S.

MlHOIR 0.

HlMOIH 7.

MEMOIRS-GEOLOGICAL SERIES.

Quebec-by Jolin A. UrcMi"* " mountain. I'rovinco of

MEMOIRS-TOPOGRAPHICAL SFHItfi.

Memoirs and Reports Published During 1911.

REPORTS.

Ri'ixirt on a part of thp V.iri I. W^li-r ■! • • • V "^''- No. 1006.
A.t«wapi.,k.t riv!;r^l.rw.1ii'e{!.'„^,'^' Vo'l'l!^"'" ''"'""■'' ''^ »''•' W.ni»k and Upper

MorleXW"lJo'n''.*"No.''ro«"""'""''^'''"'^

MiuoiR 4.

MEMOIR.S-GEOLOGRAL SERIES.

Mk«.,r 8. AV..^a^W6Vn>.. The Edn.,.n,on coal field. A.berta-by D B
M..0.H 9. ^o^9.^0c.,o,.a.l Serie.. Bi«hor„ coal baain, A.ben.-by G. S^

Ontario-by J. W Goldthwait ^'P'^S'nK in southweatcrn

MiMoia I}.

Mmom IS.
MiMom l«.

So. ll.C.olooiral Scrtr, In*rt« (rom the Tcrtii. ry Ikkadrnonlta .J tha
V. ;,'^/" "'■ '" '»<»-hy Anion Han<ilir«.h. ^ i-»rcnc.

%";H::^'i?J"j(;:;npri^" "r."""""" «••»''»""■"" '•-"'••« KirkficM
ATo. /3. U,,.l,^ealHrrie„. the cluy anil shalp .Ippoiitx of Nova Sootia
JoipreoTc."' ^ * B"'"""^l'-''y H..i«riSh Ric;Vl2.tcd by

MKMOIRS-BIOLOGICAL HERIE8.

MiMom 14. %'• f ';"W Nrnrv. N.W ,p«.i... of ,1,,.!:, c<,II«,t.,l l,v Mr. John

MiMniR t.'l.
Miuoin 21.
MzuoiR 24.

Meiioir 27.
McMoiH 28.

Memoirs Published During 1912.

MEMOIRS-GEOLOGICAL SERIE.S

'^'I'ipp'^'"'""""'' '"*"'"'• *«"'"■•"' Van.'ouv.T iMa,..l-by Charle. H.

Nn m. (Uotoakal .SVn>.,. Tho ei-a\ngy anil om ilpcMU of Phocni.

Boumlary .Ii-tr„t. British C.lun.biu-bv O. K. L^lov* •^'"«""'

kK """"■" P-^vincc—by Heinrich Rie' an.i 'loTph

^"r 'J- 'f''''''%'-^l ■'<'"■'<■ Roport „f tho CommiH^ion appoint.d to
invp^t will- Turtle mountain, I r.nl<. AllnTtn. 1(111 "P""'""" ">

Andrrw r""'!" «^ "• " v"^.'"' """'""yof «t<-..pr.M-k lake, Ontarir-l.y

laki', l>ntariu— by Charles D. Walrott.

MiHoiR 18.
Memoir 31.
Memoib 17.

Mrmoir 35.
MiMoiK 33.
Meuuir 38.

Memoirs Published up to Oct. 15, 1913.

ME.\tOIRS-OK(>[.()GICAL SKRIES.
'^ Yo'ui^™'"""''' ""^"'"- ""«'"'"' 'l'»'"'^<. ^''W nrunswick-by G. A.
%. D'.OUr'^i"" *''■""'• ^^""•"" •'""''•'• ■*'"•'"'■ Territory-by

■'^'u";-disSt"i';iT'';;i^'V^^

by Morlr^y i:.' m^l^ "'''"'"'"« "'^'•""'"' "' '''""i"'- ™unty, Qun._

■'^'ilAn^'?; «'<;"'"fli™i .Smf». RcoonnBissiinnc olc.nK the National Tranv
contin.ntal railway in Houthrrn (jiK.bri— by .Ir.hn A Dross™

-by W^'n^Tollin^"'' '^'"' ""''"'^ "' <^=^«>-""«J« Mini-8 Divi^on

No SI a.uUmcal .S.T.f«. Goolotty of ttic Xorlh Aitiorican CordillorH

at the forty-ninth parallel-by Reginald Aldworih Dal^>- Part T

Memoirs in Press, Oct. 15, 1913.

Memoir l'J. ^°- »'• <'>«'?""'' *">». Clay an.l shale dcpo.,it, of the western

Mr«n.n t? P'";,"'J,'^^»<' art, ")-l'yH.mrich Hies and Joseph Keele

Memoir 37. ^^.J?, 6t„/<,e,ca/ .Series, l, rtions of Atlio district B^C.-by J). D.

Memoir 23. ^'^^/^'^'j-OJ^^'/ertV, Geclo«- of the coast and inlands between tho
BfSJrolt ^''"'" Charlotte sound. B.C.-by J. Austen

MiMoni 40.
MtiiatB S3.

liuioiB IB.

MiMoia at.

MlMuM 38.

MiMoiii 30.
MlMOIB U.

MiMoiB 30.
liiiiow an.

UaiKMB M.

Wilx.n.

G»iilu^itfal Strift.

B.f.-by C. H

Ufitniliral Stnn.

( 'iinii'l»--by W

Tul.meMi Mining dirtrlrt. B.C.-by C C»nn«ll

Ciold Held* oJ Nov. 8«oti«-by W. Mnlmlm
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OCOIOOICAL SURVCV

HoMV'''''eMn£MAN Minister; A PLow DcputyMimistsr;
RW Shock. OinccTon

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1.0

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_jj /APPLIED IfVMGE Inc

S^ '653 Eas! Ma.n Sireet

B^S Rochester. New I'ork 1*609 USA

'^Si (716} 482 - 0300 - Phone

^K (716) 288- 5989 -To.

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OGICAL SURVEY

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