INVESTIGATION OF THE COPPER BULLION CLAIMS,

RUA COVE, KNIGHT ISLAND, ALASKA

BY F. A. RUTLEDGE

* * * * * * * * * Report of Investigations 4986

UNITED STATES DEPARTMENT OF THE INTERIOR

Douglas McKay, Secretary

BUREAU OF MINES

J. J. Forbes, Director

Workon manuscriptcompleted June 1952. The Bureau of Mines will welcome reprinting

of this paper, provided the following footnote acknowledgment is made: "eReprinted from

Bureau of Mines Report of Investigations 4986."

June 1 953
INVESTIGATION OF THE COPPER BULLION CLAIMS

RUA COVE, KNIGHT ISLAND, ALASKA

by

F. A. Rutledge!

CONTENTS

Introduction ........................... ,..... 1

Acknowledgments ............ 1

Location and accessibility ......................... . 2

Physical features and climate . . 2

History and production . . . 3

Property and ownership. . ....... 4

General geology.. . ... 4

Description of deposit ... ............. .. 4

Work by Bureau of Mines ...... .. ..... 5

ILLUSTRATIONS

Follows

1. Index map of Alaska . .......... 2

2. Index map of Knight Island ....................... 2

3. Topographic map of Copper Bullion deposit and

vicinity . . . . . . . . . . . . . . . . . . .. 2

4. Claim map of Copper Bullion group, Rua Cove ...... 2

5. Geologic map of underground workings, Rua Cove 4

6. Diamond-drill section, Copper Bullion, Rua Cove 4

7. Diamond-drill section, Copper Bullion, Rua Cove 4

8. Channel samples, upper level, Rua Cove, Knight

Island ........... .. 4

9. Estimated grade of outlined area, Upper Level,

Rua Cove. . 6

g/ Mining engineer, Bureau of Mines, Juneau, Alaska.

Report of Investigations 4986.
The Bureau of Mines Investigated the Copper Bullion claims at Eud Coove

on th_ east. coaot of - aight IslAnd in Prince Willi Sound, Alaska, during

Nove~ber-Z7ember 1948 'an Iarch-Apri . this project vaO Art of the

Bureau o I S pro gZ fox'developi`g crjtic&l and strategic mitls ia":

A34sa

neft + Co, f ;.*;th 

t *SrMnem lizatii at .t1he copper ae-o> t oan the Copr tu.l46 group o . cLaims is mainly .prrhetite and oca.Jopyi ite, confined to a iortheasttrqnding shear tone in the greenstone 2,OOQ feet northwest of TRua Cove. The

propety bale been partly deve olep '. by o adits, .by a. xeor Qf crossc't&S . from th .uppr adit, and by seere. d lo d hles.

Tho e1.a`.t at Bua Cqve is oe Qif te larg'er .kno copper prospects in

Prince Wrij.isi" "S'd. d caUs of its. l tAn iil itt the old , , Y i, > Pecuaq$W *,, , 41 t0 -OV& , ..,.Sb!L ,. Z.. ,, ....

Beat6on gNe on Latouche Island aind" e siistantiai quant ty or .64-grade qxe

already developed, this property was selected for additional develoment by.

the Bureau of Mines.

The invest~it*tion was unider the-ieer eno "upe -on of G. Z. Jenae- ain

cAier, Aokal d 3anck Mii4ng Divisio uxauof M .rzs.. A Preinpfl

examinafion of the dePos>it- wap ade durlng.- 'wt by Steh Pvolt,. - mining engineer, Bureau of Mldes.

Analytical daternnatiots of pes were. mde bY F,.4'E. Peterson, chemist,

Salt kIae Ci'Brxnch, tal cl fison, Sal Xae City, Ut.

The use of the cabins on tho px",p rt belg4z to the lessee, PxFnk t.

Dickey, Bellevue, Wash., facilitated the o' hes sureau pt'ogiam. i

Drill C S resultin, fim the Bureau of. es .digprogra were

examined and logged byVW'.. ;. 8Nenhhfel6 geooist Feeral Oeologicl urSey,

Juneau, Alaska.

: Ackaow~edgvew also. ia made t.o the Conso cdted Mining and S. ting Co.

o m Cn* Ltd., jr the use of their drill .log and for the rest of -re.r

1929-30 developreit pogam.

53:,9.8. ' .: . . ' . ,.S~j S ., . . : j e: f - : ' .._j,> t : ' -- . . . .

5398 - 1-
tOQCATIC AND ACCMIBIIATY

The Copper Bullion prospect is 2,000 norhest of Cve aeet

small. inlet on the east coast of Knight Island in Prince William Sound,

Alaska (figs. 1 and 2). United States Mineral Monument 8 on the Bullion

claim 5 is located at latitude 60° t.33f_ N. and longitude 1470'39' 25" W.

Knight Island is in the Valdez miting dittriot; the recording office is at

VaLdez, Alaska. .

Rua Cove ls on the.unprotected eapterly side'f xight Iseland; coi- 7.

sequentlby, it cannt be used for a x'arbor. At present al eq ist and

supplies must be landed by small boats during fair weather on an-extremel.

narrow beach at the mouth of the small stream flowing into the sound bel1

the beach cabin (fig. 3). An qId corduroy road In the valley provides access

from the beach to the me, a di tance o-approximat 1/Ž mile.10*

iIIreia DaE~y sou1thwest Of the Copper tullion prospect is a well-protet harbor. The construction of'l-./2 iles of road would make the mine ace sible from this bay. At present all vtater transportation 4is either-V*

chartered fishing bcats from Cordova,., 7 miles east, or by the regiular mail

bcat serving Prince William Sound, 'Small-boat charter costs appaiteW $75.00 a day; the mail boat charges $. a stop plUs $Q0i a pud for all

freight.

PHYSIMAL MTATXEMS AND CLIWTE ^

The relief on Ehight Island -is ty'pical of that in Prince William Sound;

the altitUde;. of the mountains range from l.O00Q to over 3J,,0Q feet. T1be

entire regio bf' Prince W;Ifiam Sound has .beeinterleely glaciated ennuits

of the oldA ice sheet that, covered the enltie area and etftedde4 "ast iak

Island are present in many localities as alpine glaciers.

The precipitous mountains rise seeop4l from the shore of Knihl Island;

cotsequeztly, the beaches re narro*. The esstem slope of Iron muntain

(fig. 3) rises from tide water to over 2,000 feet. The Copper Bullion

prospect is on the sut;h slope of Iron Mcuntamtn and on the north side of a

dirqueliket basin that d3aits into fut Cove,.

This basin and the lowezr 8oJ0pes of the pnountains are covered with spruce,

hemlock, ad aLdqr. -nough timber for mining use gy be cut localy. -Above

1,000 feeVt the moutains generally ate, barren.

The, cl4imte of the region Is fairly mild, althoug4 man and anow are

heavy. tuhe, 24.mileIs southiest. Iatoucb Islaid, is the nearest plqce where weather records have been kept. 'The mean annualtetper6tu*ue for

latouche is 41.80 F.; the highest and lowest tempeittires recorded are2r

and 10 F.; respectively. Average precipitation, including that formed by

162.2 inches of snow, is 176.79 inches. Some snow remains in the high

mountains throughout the siuner.

5398 , 2 ,.
/74 /62° roe

'Ix ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~~~~~~~~~~~~~~I

~~~~~~~ /~~~~~~~~~~

SEWARD KNIGHT ' ISLAND X

w Mckinley ~~~ R. ~~~~~~le

/ pat O Ace ~~~~300 t- ,

Figure 1. - Index map of Alaska.
BY F.*ISLES

o KNIGHT 0

ISLAND RUA c,

~ rv Ae COVE 600 20|

.~ ~X ~~~iue2 ~~~ ne S map of ! Kngh e Isand f 1~~~~~

____ ____ ___ ___ ____ ___ ___1470401 FROM U.S.C.&G.S. CHART

Figure 2. - Index map of Knight Island.
I \ \ 020,0,,e,,!!~~~~0\11

Figure 3. -Topographic map of Copper Bullion deposit and vicinity.
i-c~~~~~~~~~~~~~~~~~~~~~~~~~~~~Z

K / @ ~~~~SCALE IN FEET

/ MARCH 1950

FROM U.S.G.S. BULL. 947

Figure 4. - Claim map of Copper Bullion group, Rua Cove.
A lake at an altitude of 600 feet is near the western edge of the basin;

it can furnish enough water for a moderate power development (fig. 4). During

the development of the property the stream flowing from this lake was used to

run a.Pelton wheel driving a 9- by 8-inch Oingle-stage compressor.

.ISTMY AND PRODUCTION

The initial location of the copper deposit at Rua Cove was made In 1905

or 1906 by Charles T. Rua, and development began soon after. By 1908, when

the property 'was first examined by the Federal Geological Survey,2./ the main

tunnel had been driven to a length of 360 feet. -During t912 the two claims,

Copper Bullion 1 and 2, were patented by Fred Liljegren.

Cn the recommendation of W. A. Dickey, the property was acquired by

Fred B3, Snyder of Minneapolis, Minn., in 1916. It was then optioned to Dickey

and active development was undertaken. At this time the property consisted

oZ 2 patented and 16 unpatented claims. Periodical examinations of t1e

property by the Federal Geological Sprvey were made by B, L, Johnson./ in

1916, A. HI. Brooks and S. .Capps4/ . in 1922, and Fred E. Mcffit27 in 1923.

The Kenriecott Copper Corp. sampled and mapped the deposit.in 1926.

C. W. Poy was in charge of this sampling program. At this time, Dickey.

had developed the property with 1,637 feet of drifts- and crosscuts in the

mineralized shear zone on the 400-foot level.

In 1929 the Solar Development Co., a subsidiary of the Consolidated

Mining & Smelting Co. of Canada, Ltd., secured an option from W. A. Diokey

and brought the property to its present stage of development, Underground

development by the Solar Development Co. consisted of extending the workings

on the 400-foot level by 680 feet and of driving a 586-foot drift on the

200-foot level. Twelve diamond-drill holes, whose combined length was 2,073:.5

feet, were. drilled from the 400-foot level. Cne hole 251 feet long was

driven from the 200-foot level. The option held by the Solar.Develotment Co.:

was terminated in May 1930.

Upon the death of W, A, Dickey, his option was transferred to his son,

Frank H. Dickey, Bellevue, Wash., the present (April 1952) option holder.

The Rua Cove deposit and the related geology was investigated during the

summer of 1943 by Stefansson and Moxham~ /of the Federal Geological Survey.

IXTo production of ore from this deposit has been recorded.

U. S~, and 'Jr-,, Copper mining and popcigo

.2/ Grant, Uj S., and-Higgins, D., F., Jr. CoprospeT

Prince W-illiam Sound, Alska: Geol. Survey Bull. 379, p. 92, 190.

3/ Johnson, B. L.e Mining on Prince 'William Sound, laska: Geol. Surrey

Bull. 662, 1918, pp. 213-214.

it Brooks, A. H.,. and Capps, S. R., The Alaskan mining industry in 1922:

Geol...urvey Bull. .755, 1924, pp. 28-29.

5/ Stefanason, Karl, and Yoxham, Robert M., Copper Bullion claims Bua- qove,

Knight Island, Alaska:- Geol. Survey Bull. 947-E, 1946; p. 87.

61Work cited i Mosotnte 5 ('p. 5), pp. 85-92. ..

5398 _3_
P.-C M1RT AND CWVMSBIP

The Rua Cove property ccnsists of the Copper Bullion group of claims.,

The group comprises 2 ratented claims (Copper Bullion 1 and 2, petented,

U. S. Survey No. 993, U. S. Patent 16919, JTuneau No. 01616) and 16 unpatented

claims. The unpatented claims are named as follows: Bullion 1, 3, 4, 5, 6

7, 8, 10, 11, 12, 13, 14, and 15 and the Iron Bullion 1, 2, and 3. Figure

is:a rap 4ofthe claims at,-Rua Cove.

The Copper Bullion group of claims is owned by Fred B. Snyder, 1430

Rand Tower, Minneapolis, Minn., and is under option to Frank H. Dickey of

Bellevue, Wash.,

GEN=L GEOLOGY

The geo ,ogy at Rua Cove has been described in some detail by Stefanason

and Moxham.7/I The mine workings are in greenstonee. Three distinct types of

greenstcne have been recognized and described by the Geological Survey. The

mQst abundant type is fine grained, ranges in color from greenish shades to

black, and is in part very schistose. The second type is a.blocky, qark-gray

porphyritic rock. Most of the lower tunnel is in this second type, but it

can be found locally as inclusions on the upper level. The third type of

greenstone recognized by the Geological Survey is a medium-grained, gray-green

rock with the composition of a quartz diorite. In this report it is referred

to as quartz diorite.

Copper mineralization in the Prince William Sound area is usually associated with the greenstone and is concentrated along zones of shearing..

Ore bodies are replacements of the sheared greenstone by sulfide minerals,

largely pyrrhotite and chalcolyrite# the degree of replacement of.the sheared

greenstone by the sulfides differs within the ore bodies. Zones or lenses of

massive sulfides are associated closely with sheared gteenstone containing

disseminated sulfides, both may contain remnants of unaltered country rock.

DESCRIPTION C' DEPCCIT.

The copper deposit at Re' Covehas been formed within a northeasttrernding shear zone in the greenstone. oC the 4oQ-foot level, the mineralized

zone strikes N. 170 B.; it has been developed throughout a strike length of

540 feet (fig-. 5),. The width of the main mineralized zone ranges from 90 to

180 feet,

The strike and dip of the many shear planes that comprise the shear zone

are not. e tizsttant. Individual strikes range from N. 300 W. to N. 480 E. 'The

mineralization is terminated at its north end by a fault that strikes 3. 850 E.

The shear ^planes and faults dip steeply, but the dip my be i either

direction.

Apparently both walls of the principal deposit are delimited by fault

planes, which are swell exposed near the ends of the ,various crosscuts * However, several other lenses of sulide mineralization wer$ penetrated by the

7/ Work cited in footnote 5 p. 5),pp. W-9.

5.293 - 4-:
LEGEND

0 llC 2 I Diamond Drill Hole By Solor DnveloPment Co.

QO nL DiHf7{i Diomond Drill Hole By Bureou Of Mines

/ .a~ .SJ^t. Foau, Strike And Dip

40 0 4070r 00 040 .. ?. Bedding, Strike And Dip

SCOLE 10 FEET Mossive Sulfide -//W/ DDissminoted Sulfides In Sheored Greenntone

g///g -> Fine-Groined Dark Greenotone

Porphyritic Greentone

200 FEET

' ' H~~~~~~~~~~~~a ~~~~~~~~~~~~~~~~~~~~~~~~~

JI

40000To LEVEL

Figure 5. - Geologic map of underground workings, Rua Cove.
SOLAR DEVELOPMENT CO. HOLES 5-6 6BUREAU OF MINES HOLES I-3

LEGEND -

soc HoL S IDiamond Drill Hole By Solar

Denelopmenet Co.

00 3 Dlamoad Drill Hole By ____ 0.,

Bureau Of Mines 30030

SOLAR DEVELOPMENT CO. HOLE 4 e Flt _

0.53 Percent Copper _______________________________________

Massive Sulfide SOLAR DEVELOPMENT CO. HOLES 9-10

DQaeoainated Sulfides In Sheared Greeeoao

rmn-Grained Dark Greenotone

USZA I/ Porphyritic Gmenstone

\ \ Quartz Diannte

BUREAU OF MINES HOLE 2300 300

40 /400X2°#AGX/ 200 \ \zoo

\4/,,, /Wt "45,>t,, ' BUREAU OF MINES HOLE 5

BUREAU OF MINES HOLE 4

/,/,/,/,//0/,/,/,/0 0 40 00 00 400/400

D.//// H 4 / .9------- t S HOLE 9- SC=LE rEE S E 

Figure 6.- Diamond-drill section, Copper Bullion, Rua Cove.
C

SOLAR DEVELOPMENT CO. HOLES - 7-8

SOLAR DEVELOPMENT CO. HOLES 11-12

400 400 _ ___ SD.C.~~ ~ ~ HOLEIm ~ .DC.HLE8/ /

'" ''-071 _________

vo 09 _ t ,____P 300 ~~~~~~~~~~~~~ '~~~~~~~0 300 ~ ~ ~ ~ ~ ~ ~~0 0

0~~~~~~~~~~~0

_.___ HO_ 2g Diamond Drill Hole By Solar

Development Co.

SOLAR DEVELOPMENT CO. HOLES 2-3 DDH 2 Diamond Drill Hole By

Bureau Of Mines

400 1,400 Fault'

S. C. HOLE /

O 57 Percent Copper

___ Massive Sulfide

q °^t 0°@o 300 | Disseminated Sulfides In Sheared Greenstone 300 ~~~~~~~~~~~~~~~~~~300

__________ Fine-Grained Dark Greenstone

.1 , ¢ | '\ \"'| Porphyritic Greenstone

200° ¢ 200 \/\ e Quartz Diorite

40 0 40 80 160

SCALE IN FEET

Figure 7. - Diamond-drill section, Copper Bullion, Rua Cove.
%CU I- 0.50 2- 0.48 3- 0.54 4- 0.55 5- 1.05 6- 0.79 7- 1.34 8- 1.53 9- 1.51 10- 1.84 II- 1.64 %CU 12- 1.56 89-9 21 13- 1.29 9-141

14- 1.06 19- O.70

IS- 0..9 92- 0.1.59 X eg.C5U3 55900 '6 SS7 o9383 %CU tn 1 ~ 10.4128 ~~~~~~9387--o° 94_-0. 50- 1.44 1 4 9 0 51- 258 96- 25 52 1.897- 0.65 53- 0.65 9- 60.0 54- 0.78 99-105 ~~~cu ~~~~~~55- 0.43 100- 0.295 16 0 3 1 6- 0.94 1091045

17_/ -1 6 5- 0.35 Il 02-C 8 0 .40 58- 0.38 103- 1.20

19- 0.51 59- 0.6 IC 104- \128

20- 1.06 60- 0 lS- 1. 41 27- 1.04 6 0 1065- .50 28-~ %CU\X\ 22 1.26 3- 0.3 62- 01 107- 29 - 23- 1.53 35 .663- 0.48 108_-0.90

24- 1.6036- I.08 64- 0.14 109- 1. 0

132-039 ~~LEGEND

SAWLE NO. PERCENT COPPER 0_ _ 50 100 200

122 1.02

SCALE IN FEET

MARCH 1950

Figure 8. - Channel samples, upper level, Rua Cove, Knight Island.
drill holes; ane was penetrated by the 401 east drift: oIwtsi&de c the mete

mineralze, zone, as sbhown on figure 5.

A band of nearly solid sulfides approximately 500 feet long pod from

25 to 60 feet wide, extends along the west wall and across the north end of

the main mineralized zone. The original sheared- greenstoae in this. setion

has been almost entirely replaced by pyrrhotite and chalcopyrtte.. Howvevr,

several horses of barren porphyriti greastone have been exponed by the

underground workings in this section.

Most of the remainder of the main deposit is sheared greenstone, which

contains disseminated sulfides and some quartz; it also contains smaller

lenses of nearly massive sulfides and horses of tho barren porphyritic greenstone,

The lower adit, 200 feet below the main level, is in barren porphyritic

greenstone throughout most of its length. The last 80 feet, however, is in

sheared greenstone, which contains a small quantity of disseminated sulfides.

Figures 6 and 7 are idealized sections through theE diatond-drill holes.

Where no definite contact was known, the contact exposed in the drift or

drill hole was projected parallel to the bedding or banding in the greenstone.

Several opencuts have exposed zones of, sulfide mineralization on the

surface. A fault that is exposed in one opencut at an altitude of 750 feet

terminates the surface exposure' at the north;; it is assumed that an extension

of the fault terminates the main ore body on the 400-foot level. If this

assumption is correct it would indicate that the main ore zone rakes northward.

W01M BY BUBEAU OF MINES

The original Bureau of Mines program proposed concurrent channel

sampling of the underground workings and diamond drilling. However, the

Bureau of Mines was unable to procure the necessary pipe for transmitting

air and water at the scheduled time; consequently the workings were channel

sampled during November-December 1948 but the diamond drilling was postponed.

The channel-sampling program obtained 182 samples from 917.7 linear feet of

crosscuts. The locations of the samples and the percentages of copper are

shown on figure 8. Gold and silver analyses on composite samples are given

in the table Composite sample analyses.

The property was diamond drilled during March and April 1949. Five holes

were drilled; their combined length was 896.6 feet. Four of the drill holes

were located in the area north of the fault that terminates the ore body; they

were drilled to determine if additional copper mineralization exists in that

area, but no sulfide mineralization was found, except near the turn in drift

401 east. Here the sheared greenstone contains a small amount of disseminated

sulfides. A lens composed of massive sulfide and disseminated sulfide

mineralization, in approximately equal amounts was cut by drill hole 2.

5398 -5-.
I~rilliio~e~ 5~s 4i~iedfrm mthe' main Odit to- tes th ur.4AAi~sio

of the fault that terminates the ore body on th4 northi, T-he x'ebudlt~ from

this hole indicate a roll in the contact as shown on figure 6, Bureau of

Mines ho le 5.

Ap plei m rna 4 t-be-4~00;foot "level with C-bmpi~ted average analy is'of

plus -l-~rcen ~ &~d ot mius-i-percentore 'is shown on~ fi~ur" 9.It is

noted that 4the palus-l'-percent copper mineralization tends to 'fofllo the 2oe

of~ massive sulfide mineralization,

'The massive sulfide tnons were considered by the Burea'u of M~ines'as

possible sources of Lsulfur for use in pulp mills proposed for, southeastern

Alaska. Couaposites ,6f igamplL~ representing cross sections -of the main

sulfide lens were analyzed for iron and sulfuir. The following table gives,

the analyses of Fe and S for the composite samples and, the. computed analyses

for'Cl, Atd~ and Ag.

Compos It esampleanlses

I B~~~~e'roent ______ Ounc e'rerVt on

* Sa , le' : j 

23-24 1249331.45 1 .0051

45-48 I~.851.1! 31.65 .005 1

50-51 e.01- 34 & 21:11 35 .05 *

77-84 ,.9- 4 26. - 005 . 86~-87 I1.2 52.1 .32.3 05( 126-129 68-7 35 .3 1 20.2 * 0t.5

5398 -6

Int. Bu. of Mines, Pgh., Pa.
LEGEND

/ ~~~~~~~~~~~~~~~~~~~~PLUS .0 PERCENT COPPR

P I 0 / PERCENT COPPER NOT IN PLAIE OF PLAN

VJ -f .0PEEN N

SOC.EB. CIAMORD DRILL MLE N1 ULAN uEI.6T CO.

r NW- 177 SNOW IN PERT P1T COPPER

CLEV 710 FT

CALE I30 FT

JW HHIFH l~flU~~flllfflliF1B JA ii5 T

0 ~ ~~~~~~~~~~~~~~~1 ~ ~ ~ 

SCALE IN FEET

NO.PIE FROM BY MOEAU OF MINES, SOLAR EELOPT CO., CR0 KENWECOTT CORP. JAN. 1950

Figure 9. - Estimated grade of outlined area, Upper Level, Rua Cove.