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R. 1. 4168 JANUARY 1948

UNITED STATES

DEPARTMENT OF THE INTERIOR

J. A. KRUG, SECRETARY

BUREAU OF MINES

JAMES BOYD. DIRECTOR

REPORT OF INVESTIGATIONS

MIRROR HARBOR NICKEL DEPOSITS

CHICHAGOF ISLAND, ALASKA

BY

W. M. TRAVER, JR.
R. I, 4168,

January 1948.

fREPORT OF INVESTIGATIONS

.:

UNITED $.,TATES DEPARTn ENT OF THE INTERIOR -.BUREAU OF MINES

MIRROR HARBOR NICKEL DEPOSITS, CHICHAGOF ISLAND, ALASKAI/

By. W. M.. Traver, Jr.3.

COUTENTS

"' ' ' ' ' * ~~~~~~~~~~~P~age

Introduction ................. * 2

Aaknowledgments * .*.. **i** * .. ...... 2

Location and accessibility ............ * ...... *

Topography ... ................ 3

Climate 4..*4**4*+...**t.. 4

Timber ............... 4

WTater . . .......................... . 4

Power . .............. .. ........ 4

Camp facilities .' .......... 4

History and.production ............... ,.' ..... 5

Ovrnership ..... '...- , .-..... *-.... 5

Geology . .. ..... - 5........ 

Investigations by Bureau of iiines r. 6

Disseminated sulfide deposit ..... ... ... . 6

Deposits near the head of Davison Bay ....... 6

Deposit on Fleming Island ......... .,... 6

Core drilling *.*... .- * 7

Diamond-drill sampling ... .. . 8

Pit sampling ,. ...... 12

Bibliography ........... 13

ILLUSTRATIONS

Following

Fig..' . . 'page

1# Territory of Alaska index map, Mirror Harbor} Alaska .. ... 2

2, Location map, Mirror Harbor nickel deposits 2

3s Geologic map of M1irror Harbor nickel deposits 4. .*.. Po 4

4. Map of disseminated sulfide deposit, Mirror'Harbor nickel

deposits . ..... . . v ... -.. .. ,, ,,* .. 4 ..#t. 4. 4

. * *. **..* 6

5o Davison Bay area No, 2, Mirror Harbor nickel deposits ,,.. 6

6, Vertical section through holes 2 and 3 *........e.........* 6

7. Fleming Island outcrop and mine workings . ....... 6

A) The Bureau of Mines vaill welcome reprlnting of this paper, provided the

following footnote acknowledgment is used: P1Reprinted from Bureau of

Mines Report of Investigations 4l68.1

.g/ Mining engineer, Bureau of Mines, Denver, Colo.

1912
R.I, 4168

ILLUSTRATIONS (Continued)

Following

Fig. page

8. Weticaection throughhole-No,1..- ........ ,,,5, ... 6

9. Section through hole 4, Fleming Island .,...... ,,.,., 6

-. 0.!. eetion throu-gh hleea.-.5.and:6,Fle~lngJXslnd * *.~, tfr***K^ '.;:4 

INTRODUCTION

As a direct result of the second 1W"orld JVar, consumption of nickel in

the United States has increased to such an extent that it has been considered

timely to investigate undeveloped deposits of the nickel minerals,

Funds:.iwere made available to the Bureau of Mines in 1941 to investigate

the extent, pecurrenoe, and quality pf.j4pce. ores in the: Mr or Harbor area.

The Federal. Geological Survey /.pasppe.d a stud.ed the ar.a ,4ring the sumner

of 1941 and.Rolert S. Sanford.,, an eng-neer.of .,e Bureau of Mines, made a

preliminary.-examination. in Juo. L942.. . A. pontract for drilling the deposits

under the direction.of.the.aauthor. was f.et.* 4 July. W942. L4 . .. .. .. ..... ......... .. ............... . .... ... .... ..; . .

ACKN0'V.DGLMNTS...

This pappr. is onwe of many repprig. oPp yarious aa ts- f the Bureau of

Yines program initiated in. Augus. L.939. by passage of the.tratpegio Minerals

Act, the scope of whi.ch. was, groeatLy. xpandedk by, subseuynt e1gislation.

Some- of those, papers are pVThished aps war mineral repos, others as

bulletins, tephtnical, paper5, reports of: investigatignp, and information circulars of the. Bureau of Mines, or.in tec.hn:ol journala,

In'its. program. Pf. iavxestigPtiop. pf, mLigrgl, d6poqsit_, the- Bureau of Mines

has as its prijiary. pbjeptivje. the nopr.e efective um4t4¢ .t4.on4 of our mineral

resourcesi. to. the. end that. they, mxae. the, grpapt poq.isble cqoptribution to

national'.ber-urity. and. economy.. . It. is. tjh-e ppj%.oy. of ,the Bueau to publish

the facts developed by each project as soon as practicable after its conclusion. The Mining Branch, Lowell B.. 'Ioon,,,chief, conducts preliminary examinations, performs the actual investigative work, and prepares the final

rep't. The Metallurgical Branch, Oliver C. Ralston, chief, analyses samplea

and peroqpjs the benef iatiop teots,. i , .. ' , .* 

..... .sti.gation.' . : ..... :'.J 1 ' . j,,:,.,"'in 

, T Uiror ,he Harbor project was a .prrt, of, ,a. pr.ogram' for the investigation of mineral~deposi tsin Alaska, under t.he geneqral, supervision pf ', S. Sanford,

acting. diy.sion c~hief

Acknowledgment is made to. lilliam- T. F coaa and George C' ,Ienned for ..... ~~ ...... .1 . I . . ........ I w . . I I ' . -.. .... .I ., It ... geologic maps and cooperatioq in,.,pakin` dri ,,hole kter e A on

y/ pecor5,. Itlrl Wi~i4~~ T}iE(ptDeposits' on the WTest 'Oftof

Chichagof' Isand, Al~s1. J S._Geol..Surve. RullS 9 6-I, pp. 221-

243, 1942.

1912 2
SIBERIA

DOA4//V/ON/

y {t *C GU/LF Of ALASKA 'N

H05 LOCATION C

Figure 1. - Territory of Alaska index map, Mirror Harbor, Alaska.
/ Skoqwoy

Lr# Pelln OWN S Eo9 /e River

Figure 2. - Location map, Mirror Harbor nickel deposits.
R.I. 416$

LOCATION AND ACCESSIBILITY

Chichagof Island is one.of the most northern of the islands of the

Alexander Archipelago. of southeastern Alaska (fig, 1) and is in the Sitka

mining district., The prospectsreported herewith a-re confined to an area

east of Davison Bay and to one deposit of concentrated sulfide on the north

end of Fleming Island at the entrance to Mirror Harbor. This area is about

rmidway between the south entrance to Lisianski Strait and the town of Chichagof at north latitude-570 47! and wept longitude 136° 1914 By water, the

deposits are about 150 miles west of Juneau.and 70 miles north of Sitka. The

area is 12 miles north of Kimshan Cove,.which is headquarters of the HirstChichagof Mining Co. and the closest post office and point for receipt and

dispatch of freight and express shipments.

Navigation along the..-west coast of Chichagof Island is hazardous,.owing

to the numerous rocks and reefs, but a detailed chartl is available for the

guidance-of boatmen. Mirror Harbor is inaccessible to large;,ocean-going vessels but can readily be reached by.smaller boats. Mirror Harbor and West Arm

afford safe, protected anchorage from storms, which are frequent on the Pacific

Ocean in this locality. A comparatively safe course for small boats (fig. 2) fry

Juneau is subject to the hazards of open ocean travel for only about 7 miles

between the south entrance to Liaianski Strait and Mirror Ha~rbor,

A weekly schedule betwnoen Juneau and Sitka is maintainedby a motorship

that calls at both Chiohagof and YiUmshan Cove for mail, express, and freight

when the mines at those towns are in. operation. Freight rates to Kimshan

Cove from Juneau are %7 a ton or $0.17-i a cubic foot, whichever is greater,.

Airplane service is no longer available to intermediate points on scheduled flights -of the Alask~a Coastal Airways between Juneau and Sita,. 17hen

there is enough traffic to warrant it, stops are made at both Chichagof and

Kimshan Cove; the fare is $20.88i including tax, from Juneau to Kimshan Cove.

An excellent foot trail built and maintained by the U, So Forest Service

extends from Portlock Harbor to White Sulphur Springs, on Bertha Bay, and

crosses Falls Creek on a bridge east of Davison Bay. A branch leads to

Mirror Harbor and 'lest Arm.

At present, with the curtailment.of gold mining at both Chichagof and

Kimshan Cove,.the only means of transportation directly to and from Mirror

Harbor is by chartered small boats..

TOPOGRAPHY

Most of the west coast of Chichagof Island is extremely rugged, with

mountains rising abruptly from the coast to 2,500 feet; occasional peaks rise

to over 3.,000 feet.

A low coastal plain almost eompletely surrounds Davison Bay. This plain

averages 2 miles in width but reaches 4 width of 4 miles at one point, The

fy U4 SD. Coast and Geodetl. Survey o, 825'8,

1912 3
general altitude of thisc-ads`.a.p-lin l`ss than 150 feet. The plain is

an area of low, rounded hills rising above sammps and small ponds. Muskeg

is as zimuoh as 5 'feet in dopt~htere-and is underlain by a.rhin. laye of hard

pan.'; The land slopeis gently to the inner.e4ge of the coastal plin, from

hiech point' it rises precipitous1y :ta .t4he higher elevation5p*

' '' . ' . . . , . .., A <. .~~~~U~k.±.~j'4 .

;; z -- .-.. . .:. CLfIMATE . ; !. ' ' }.

.'; The cliwmte is.cool and moist; Precipitation is heavy and chiefly in

;-the form 'of rain. -Average annual predipitatiQn.at Iitka is 88 inches,. but

Pas'much as 23 inGheb has been recorded in one month .

The U. S. Weather station stabliqhed-at- .shn Ccqve in August 1940

reported average annual precipitatikn of 120 inches, maximum temperature

'570 -F. and-&ihimi 300 F., between thatz4ato: 8$d July, .l942,. ;

- tMintte snowt ar. not-reported to rea4h.,g~ea-t depj4h.e!eept at the; igher

altitudes'. Tearkbound mining is possiblJe.;

SprWee :hemloek, and cdad gr.6* .abuudantly i -the: viepnity; of the deposits, but very little of it is suitable for mine purposes, 14ost of the timber

+ 4 sedIby- operatingmiftes in. thidistrict i$ obtained froi; Bar'nqS lsland.

4~~~~~~ ' ' i; ' !, ~ ~~~~~~~~ , ' 

.:~~~~~ . .. -WATE'';R '' , { - .. w.;!.. 

*L.:.@. , .4 t ' t 4. ; '.i... . , ,,0

A small pond near the center of Fleming Island could furnish enough

*. *ter fdr' domesti. taS e and for ;th& operat n. oft' a manll, pant, ,A 1,,0CO-Coot

,pitpe liae. woUld b1W eeded. For 'a -pertantent_%nd -ur~Thd4ed frepfrter strpply,

-:.X8.udl'd be neoesstry to install a pipeline-fror th- falls i.Lllp 0Greek, a

ci'di~tancaedof 10'006. feet. This- ould deliper water at-'a 400fo-tqhead aan provide adequate fire protection and might be utilized to furnish limited power

-f $ae'tation of asmall mining' .,its.- E ...... ....... ~ ~~ ~ ....

4'~ ~~~~~~~; -4 ,s '

No electric power is available. Early operators in the district applied

.,,to 'the U, ritbd States 'De1aitment b of Agriculture. f*, ,w,,hyd9-electrc power

>.and'.trarxs£:gsion. liha'permts, One wae:-for. the util4zation of Y41,ls- ;Creek

with a drainage basin of 12 square milsf srit which,-, a flume 700 f;et~Jo.ong

at the head of the falls,-riould give a head betwveen penstock and water wheel

of 266 feet and deliver 2,500 hMrsepower through a transmission line of 9,600

feet. The other would utilize Porcupine River, which has a drainage basin of

16: square wilt--.r;4 ih .witb : ei2-70O:feet. .orng,- wpga2 gisve a head between

penstack.and, mater fteel. oflightly less t1B:2-0 2r.-ng £ee. deti ,,909

horsepower through 16,500 feet of transmission line.

... APFACILITI .; , ..i

'.^ . .f. '., ',' .4 ; . , ,. . ''.14 ' . ;,. ' ,' ;, 4 "-' , .: , -:. ,',_.,',. -,', ';: ;' ,,...

There are no buildings at the property except a small bunkhouse, which

will accommodate 3 men, and ;.nd Rb ic;a 

1912 -
;?ky~ ~ ~ ~ ~ I'' ~~~fff 

5hog ~ ~ ~ ~ I'. ~ ~ , 

o~ ~ Ij:,.:i'

M>A,1 ~ ' Middl IeGOJ? It

* ( WOxrie roaD .

6 C/<7oCormorYn Aurora 

V Wel9/e

F\Nig-Iue OrO3crk

ml ;Oant-e &rlvup

A~fefon17oI74vA;osedl cOnyw6ocke

§ A/oslw C/oiI77s.

6G AurorO0 Cloims.

IVO-oif/e Wirom 41 cSOS8l &J/19-P/ate 36

0 /000 2000 3000

r4arch 1943

Figure 3. - Geologic map, Mirror Harbor nickel deposits.
R.I. 4168

shaft. A 12- by 16-foot office building was constructed by the Bureau c-f

Lines before exploration was b egun. A 16- by 40-foot house float was rented

at Pelican City and ias towed to the deposits to provide quarters and boarding accommodations for the workmen. The house float was removed when exploration- was termndirated.:..

'HI$TORY %AND PRODUCTION

Authentic historical information 'concerning the deposits is meager.

Discovery was presumably made in 1911, and original locations were made at

that time and relocations.in 1915, under, the uname of the Juneau Sea Level

Copper Lines. In 1917 the name was changed to the Alaska Nickel Mines.

No ore shipments- have 'beert mdde as a result of development work on

:.Fleing''Island, except- for small avounts. used for testing purposes. Very

,little of the mined ore is left on the'dumps, and a considerable quantity.

is reported to have been.taketi by passing boatmen for use as ballast.'

The ore deposits are controlled by Carl Vevelstad, of Petersburg, and

associates. Only the claims that cover. the particular mineral areas discussed in this report are shown on figure 3, Information as to their location was furnished by Carl Vevelstad, one of the oners,

;EOLOGYW

-In the area between the south entrance to Lisianski Strait and Dry Passage, the older stratifiod rocks, mostly composed of gray4acke' and greenstone,

have been intruded by three large stocks of igneous rocks. -The earlier rocks

have a northwest and southeast strike, are considered to be older than lower

Cretaceous or upper Triassic Age, and locally have been highly metamorphosed.

The igneous rocks are, flow rocks and intrusives representing granite,

diorites, alaskite, aplite, morite, gabbro, and andesite.

Significant sulfide concentrations, either as disseminated or massive

ore, are found only, in three areas of the stock in the vicinity of Davison

Bay. Areas 1, 2, and 3 are shown on figure 3. It is exposed only along the

shore lines of th6 coastal plain,:the remainder northeastward' being concealed

by vegetation or muskeg, and a possibly much larger area west and south

extends under the ocean.

.1inoralization is present in. all the 'rQcks of the stock, but the better

showings are confined to the norite. The ore concentration, both disseminated

and, maoive, are considered to be the' results of magmntic segrations and are

mainly pyrrhotite, pontlandito, and chalcopyrite.

5/ So footnote 3,

1912 -5-
R. I.. 4a68

INVESTIGATIONS BY BUREAU OF LA1NES

The ores at the three locations 'in the stock were explored by the

Bureau by diamond drilling. These included (1) a disseminated sulfide deposit 1,000 feet southeast of Davison Bay, (2) exposures of a concentrated

sulfide deposit at the head of Davison Bay, and (3) a concentrated sulfide

deposit on the northern end of Fleming Island.

Disseminated Sulfide Deposit

During the summer of 1941 the property owners excavated a total of 45

pits under the direction of the Federal Geological Survey to expose the underlying formations and permit sampling and examnration. 'Subsequently, some

of these pits were further extended, as shown on-figure 4. Complete delimiting of the area would have required more drilling than could have been accomplished in the short working season. Therefore, in order to test the depth

of mineralization, core-drill hole 1 was located at a point selected as representative of the deposit.

Deposits Near the Head of Davison BayL

Small sulfide outcrops occur at points marked A, B, C, and D on figure

5. The outcrop at'A is by far the largest of these, and that at B was completely obliterated in attempting to trench around it. C is a slight concentration surrounded by some disseminated sulfide, and that at D is covered

by water at high tide. The rock from this latter exposure shows only small

amounts f nickel or copper minerals but contains some graphite, which vas

also observed in slightly mQre than 1 foot of core from each of two drill

holes.

Short holes (2 and 3) were drilled under the outcrops at A and B to determine whether they extend to any appreciable depth below the surface. Figure

6 shows a vertical section through these holes.

Horizontal and vertical extent of the larger exposure is virtually limited to the surface, It has been eroded around the base, and portions of

barren underlying rock are exposed. There is nothing sug3estive of a workable

body or any apparent connection rith any other deposit. Uineralizatioh, al- V

though similar to that at the shaft on Fleming Island, is of no commercial

importance. a

Deposit on Fleming Island

The outcrop is partly covered by Fleming Channel at high tide, and a

small part is under the mine dump. Trenching delineated the outcrop as

roughly elliptical in shape, wmith a long axis of 40 feet and a short axis of

27 feet. Limits are well-defined, and there is nothing to indicate greater

longitudinal dimensions.

1912 -6-
Contour / 0 Pond

",c^4 %\ ,\ 4\ > \J

S~~~~~~~~~~~~~~~~~~~~~~~~

- ;-.n~r /nctdb-3rr o/ \\ 3 \

I s

ContouInterva I0Fee

Oigunl FZ respec- Plitpo ismntdsliedpst ir abrnce eois

'~. -~ PitOExtension

Modified USGS from Buletin 936-I. Plate 3

Fiur 4.-Ma o iseintd-ul~e eost Miror abrnceeois
DAV/SO IS LAND

BAY

SHALL OW

,, ,'-. .. PASSAGE

LAGOON WITH SAND BOTTOM

Few feet deep at low water

1* 4.~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~A

LEGEND

Amphibolitc Noritr Gevro-dirite Peg-fit. Concentreted Sand and

/ + +; ++, * norite sulfide outcrops rubbb

0 /00 zoo MODIFIED FROM U.S.G.S. Htigh-water Shoft Trench

AtarcA /943 *Scale in Foet BUL 936-I FIG. 25 shore line

Figure 5. - Davison Bay area No. 2, Mirror Harbor nickel deposits.
Hole Alo. 2 'H/ole A/o. 39 HI/GH WATER

,rL E VEL

Section a-a', Fig. 6

Ho/e No. 2 Hol/e Nlo. 3

CORE SAMPLES CORE SAMPLZES

JAMPLE PERCENT FOO TA GE SAMPL PERCENVT FOO TA GE

NO. Nli Ca From |To No. Ni Cu From TO

/ 0./I 0./0 2.0 4.4 - - - 20 //0

2 1.86 .40 4.4 5 6 / *O.O/ 0.03 //.0 /5.1

3 * .0/ .03 5.6 /0.6 **2 .03 ,02- /5./6.4

- * .0/ .02 /0.6 3/. o 3 * .0/ .03 /6.4 21.4

4 * .0/ .03 31.0 36.0 - - - 21.4 40.0

**5 * .0/ 10 36.0 373 DAVISON BAY

6 * .0/ .04 37.3 41.0 CHA'NNEL SAMPLES

* Less Man 3AMPLE LENGTH PERCENT

** Sample shows Graphiie NO. Ni Cu

./3. 5.0 0.14 0.18

0 40 8o /4 5.0 .05 .03

ScAC ,.v FT r /65 5.0 .53 .38

Figure 6943 16 1.5 .86 .30

Jelected Ore 1.36 .77

Figure 6. -Vertical section through holes 2 and 3.
* 0.C. HOAt At.6

X / As_ X C3 ~~~~~~~Concentrated- .ulfide, I-vOe/ crop 75'Leve/

\i Wat /eve Ve/etation & Mine Dump

\\ Mineralized t ,orite

0 \1\ Ace -° D~B. 20°* Ho/e No.4

\ l > an s~~~~~o/¢ ntatd suld8

Scale in Fe~t 1212 Hale Mne d

March /943 1 DO. Able No.7

SURVEY AND GEOLOGY BY GEOLOGICAL SURVEY

Figure 7. - Fleming Island outcrop and mine workings.
Hole No. I \ /n~cel InFeet

D Pi3 em/noted Sulfide 9 p~mrfide Zon4

40 r Pit /0-Projec to dI

arrnferred Contac r 1

S4/fide Zone ~_ _ _

~ MConote tieact

a Sw/fide Zone

L EGEND

A Hu vium 0 50 /00

'~ o Bueau Mine Sarnle~sSURVEY AND GEOLOGY BY GEOLOGICAL SURVEY

Figure 8. - Vertical section through hole I.
~~~~~~~ln AD. Halt No. NOa

Shaft AA ole#YQ

,D.D. Hole No. 4

LEGEND

Alluvium , .-O.25% N

Norite , Barren ,O

Abrite*, Minera/ized a A

Horn fe/s

Concentroafed Ore j0l /32.7 0./O7.Ni Est.

|>,'' tDike Andesite

-Kn o wn Orc

1-19 Sample Numbers I LO2Ox Ni Ev

Dril/ Log by 6eo/og9ca/ Survey

200

Scale in Feet

Mcarch 1943 2

252F0

Figure 9. - Section through hole 4, Fleming Island.
'% AVwD.MleN5

LEGEND

U | I 1:' L. Alluvium

Diorite

i. I ES NSor/te, Barren

Nor| af, Mineralized

3J x HI rnfe/s

Concen trv'ed Ort

0 -50 Gabbro

Sca/e in Feet /-9

March 1/943 /_/ Sample Numbers

Drill Log by Geologica/ Svrvey

Figure IO. - Section through holes 5 and 6, Fleming Island.
R.I. 4168

Considerable information relative to underground development and geol-.

ogy is contained in 'eports of examinations made by engineers and geologists

durng 1917 and. 19l0. ; .-

A 6- by 8-foot shaft had been sink east of txe6'outcrop prior td. 1)17,

and levels at 75 and 175 feet were driven from it, These workings 'are

flooded, and water -stands. within 6 ;f eet of' the :collaV,.

The reports concur, i ithe .,i .that the,drif rom.th6 .sbX n the'

75-foot level exposes 32 feet of concentrated ore oni the long aads of the

ore body, and crosscuts from, this drift.expose 10 feet. of ore on the short

axis. These crossouts were terminated' in ore. Deve opi~ent work ofiith6 175-

foot level is reported_ q.showin ;,a high ly ractured area. of 41issem ted ore

with some' oncentration''''ahng £fultsIip'

.,Anormal fault enco~unterqd on the lower level is n6t,6o6nsidered to have

displaqed the or~e appreciably, and on,.thea lower side of thefaultJit wquld

be' Tound in a direction'sLft t'fr6n'the kings. This -is the'-area---e*;--

plored by the Bureau of Ml s. . '

The advantages of unatering'thershaft-' core drilling underground

were largely offset by' the difficulty Qf empl6ying expe'ienced workman .i'id

obtaining critical materials and equipment.. ,It Nmq ainticipated that 'co4arable results would bS &fiWiiad by atr t i located surface drill holes,

requiring some additional drill footage but saving the expense of pumping' and

shaft timbering.

The plan of Fleming Island outcrop and mine workings is shown in figure

7.- Lbctatios oi drill' holes alsc are sho'xn;^numbered in the-rder in vi1{i6hthey were drilled. Figure 8 is a vortical section through drill hole 1,

Figure 9 is a section of drill hole 4 iitih the surface channel cut, and figure .10 -i a section of drill holes 5 and 6. Spctions were not.made of drill

holes .7-and 8 as no ore was encountered, but they.arep projjqcted on the, seetipon shown in figure 9'

The ore, as disclosed by core-drill holes and outcrops, 'surfce appears

to consist of ir~regular pods. of' high-grade ore, none Xf which a'e .ofcany

great dimensions> surrounded-by areas.of.norite. In plac a6the norite contains slight .disseminations Qf minerqa nr d ii other 1 its. svizrtually barren.

* These changes, from ore, to waste are abrupt and irreguar and4 suggest that in

mining some qeffort.at sorting would be necessary ' .

eCORE DRIt 4 ING

One of the drills from the Bohemia Basin nickel project at Yakobi Island

was moved to Mirror Harbor, and drilling continued by the same private contractor under the direct supervision of a Bureau of Minos engineer. The drill

W Reports of examination made for the ominers of the Alaska Nickel Mines by'

E. E. Fleming, G. T. Jackson, Ralph L. Healey, J. C, Rogers, and Horace

V. Winchell in 1917 and 1918, made available to the Bureau of Mines

from the files of the Alaska Juneau Gold rMining Co.,, Juneau, Alaska,

by J. A, W'dilliams, general superintendent.

1912 -7-
R.I. 4168

rig was a standard portable rotary drill powered by a Model T Ford motor,

recovering bores of standard "BX", "AX", and "IEX" sizes through.adouble

core barrel.

The contractor's equipment was unloaded at Mirror Harbor beach on

August 16, 1942, and drilling was completed and equipment was loaded on a

scow for transportation to'Juneau.on.September 24, 1942.

Taqble 1 gives pertinent data.concerning drill. holes.

TABLE 1. Diamond drill hole data., Mirror Harbor nickel deposits

Collar 1 ,,

I elevation, 1Length,;.| Feet ;Percent. core

Hole'. feet . Bearing. Inclination | feet . in ore. recovered

Disseminated sulfide deposit. .

1 60 ,I .. , N. 400E. -50 ° 263.0 1 78.5 95.9

| . :!, , Davison Day deposit t. ...................- l:

2 , , .. 6 | .f N. | 45.son5 E 2n22~t 1.2, 90.3 

3 ...... S. 240 W. . -330 40. 0 0 91.1

Fleming. Island concentrated-sulfide deposit

4 .,, . ;., 22.5 : , z N, 490 I.. -55 -136.9 "28. 91.5

5 1 12.0 S. 41 i -60° 158.3 8.0 93.9'

6 . 1 12.0 ! s. 410 W. - 450 143.8 28.3 94.1

7 '..... q . ' 14.0 | N. 499 W7. l -$89 . 235';4 0 ." 96.5

8 ...... 22.5. N. 4901 I .: 252.0 0 94.1 _ IDIAiiiQND-DRILL SAUPLING :;

Cores were filed in wooden core boxes.with metal dividers until logged

by George C. Kennedy, junior geologist of the Federal Gealogical Survey,

after which they were split longitudinally, one half going for analysis and

the duplicates retained on file at the project office. .

Standard metal,"sludge tankstt'were usedc, and, cuttings were. recovered in

all holes whiledrilling in ore*- Coree recovery was high, and the cuttingswere, discarded when the core wvAs removed from-theholes. No cuttings of -

samples were sent for analysis.. Core analyses are shown in:. tables 2, 3, 4,

and 5, Table 6 shows the lengths and analyses of 6 surface channel samples.

Table 7 summarizes the channel and core' sampling.

* -. , *: -

1 914

1912--
R. I. 4168

.~..TABLE 2. '-.D~.iX1kbld

F6 tage,4~. - Samp er orQe nal 8~s, .percent

V r T61- 64 lngt ft.

4.5 i%'.5 f I O 0.21 1 005

95 j.145 2 5. 15 .01l

14. 5 )-9.5 3 1 5.0 fl.*03

24.5 .29.5 5 .073

29. 32.5 6 *~3.0 .0.)

32.5 '34 0 7 . 15.3*0

34.0 O3~0 8 50 .12 .0

39.0 44i,.1 9 , 5.1 .10 .02

44. 47-.0 2.9 I

47.0 5J..5 10 4.5 0.04 Q.02

51.5 56'.2 I11 .1 4.7 .08 ..02

56.'2 60.9 112 4.7 ' .45

60.9 66.0 13 5.1 .07 ,024,

664~0 I71.0: 14 5. 0 .10 .02.

71.0 76,0 ~15 5.0 . 0- -.02

76.0 80. **0164.0 .0

80.0 83~ 17.j...O ~802:

V 7 8.~5 120 ;1029

83.0 880- 18 5.0 0.03 b.'02

88.0 !258:0 2,9 170.0 -:... A

D. D. hol.e 19 , 78.5 0.120 0,029

P it 8 .. ..... P. .~ '.312

PitlO. .- OO-- 3'00$

Pit 12 **:;*~ . 10..0 - 40 O--4

123.5" .172 ~~49

*0Qverbiirden.

*~*Smp~enot analyzed.

1912 -9-
R.I. 4168

TABL35%- .D., , Hole 4

Footae- antesis, Sample ipercent Core 

From- _ _ Sample Jl ngth ft. I Ni Cu

0' .1 4.0~ o __v I -

4.0' 52.5 48I --

52.5 57.5 1' s*a 0.05 -.0.06

57.5 63.0 2' 5.5' .10 j .04.

63. 69.0 3' 6,aC .07 .04

69.6 75.0 ! 6.0 ; .l j. .09

75.0, 88.31 1*3.3' -_-

88.3 89.3 - 5 1.0 ! 0,22 0. 0 -

89.3 91,0 1 6' 1.7 3 2.88 1.54

91.0 194.01 7 3.0' 06 . .20

94.s G 95.1 8 gl.l I 199 ;, .gl

95.1 97.4 i -9' 2.3 ! 10 04^

97.4 1100.8 10' 3.4 004 .03

100.8 ,1058'8 1 11' 5.0' | .48 .48'

105.8~ 110.3 31l2 4.5, t 44 ! .30

110.3 l11.0: 13 ,7' 4:20 1f .83

111.0 I'113.7 !14 2.7 .07 . .05

113.7 '116.3 15' 26 1 4.39 2.77

! |.956 28,0 .571

116.3 124,7 16 g.4 0;13' 0.8

124.7 1l25.0 17 .3 I 1.05 2.121'

125.0 131.0 18 6.0 .20 I .16

131.0 1136.9 1 19 i 5.9 .18 .14

'*Overlurden.

-",,**Sample not analyzed.

T1ABLE 4. _D. D."Hole 5

Fo tage Sample Core aggyais, percent- From-' To- 'Sampll length, ft. Ni f Cu

1 2.01 .*-..1

2.0 13,0 -11.0 ! .

13.0 18.0 1 5.0 1 0.07 I 0,04

18*0 21.5 2 3.5 .05 1 .03

21.5 129.5 -\**t 108.0 -_ -

129, 1-34.5 3 5. 01 0.09

134.5 135.5 4 1.0 1.°70 .44

135.5 136.7 5 1.2 j 4.23 i .60

136,7 1137:5 6 .07 j 03

137.5 1138.3 7 .$ i 4.30 , .17

1383J 143.0t 1 8 4.7 3*'02 1 .60

_____ ___,_ *8.5 2X78 - .487_

143.0 148.0 i9 5.0 0. 01 | 0.02

148.0 158.,3 10.3 - *Overburden.

,,-,'-Less than.

iPMN*Sample not- analyzed.

1912 -10-
TABLE 5. - D. D. Hole 6

Footage S Obre 6._pe__nt

From- To- Sample i length ft..., asi percent

0 2.01 -s 1 *--. i t. -.

20,m 350 I r 33. - .

35., 4L .. 0 l 1 0.21 0.09

; 43.$K4%' - 2 2.3 0.97

t ., (45.' 73., -t .9 - -, . -

73.7 j -72 3 2.1 Q.0.5 j 5'0.15

75.8 100.7 -24,'*9 ; -

100. 7 ; J.. Z.z;;0 t 0.87

104,0 i l0c8*. b o

10$4.0-Po12i .o t 6 -4.9 I t J7w79

11130 1- I 7 i 83 5"t2 1 2R,9; L1:~~~~~~~~~2 3 - L L *31 -04II W .. :'!21 

lL5.0 ; 7Q , .1203 '370 2.... 2S ;:.

122.0 1125.7 !1 3.Q7 'io . 7 o 129. 3.3 . Z 6Z2' 3.5$

i..,.. 8.3. j J.560 *2.014 

129 ;rOW3.8 ; . - 1, L.. .. ; -. '.

T~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ..

e--Saxnple not analyzed. -;^ .

'ABLE.6 .. .- Surdace channel ..

(-See CigT9)7T.

_.;.^ 4-: Sa e ,ore analyios, percent

Sample I~ength; ft. Ni Cu : ... :

2 . ... 5.90 '1.08 - 47'

3 ..... 5.0 1.20 . 2.24

4i,,.. 50 5.s i 8$ ..89

5 ai 5,o0 .08 1 .81

6 ... 4,... 3.21 . .84 _ _ _ 29.0. . 1.L45L 1 1 '-

TABtE: 7,o Totals -

'- 6Eample: ' jCore analysis, percent. -'

_ length. ft. j Ni : Cu

Hole 4 . . . i 28. I: 09561 0,571 .,..'

Hole 5 ...... 8.5.5 2 876 - .487 

Hole 6 .. ... .283 o14 2 14560

-7i '864. ±~ 1.670 0. 99;2.

Channel -............. l. 29.0 - 1,458:. 1 3⁄4016 j.

Total average . ..... * , 9308 .1. 0 999

Channel and hole 4? average 57,0 .1.21279

Holes 5 and 6, average ,.,, 1 36.8 . 2213 1.- -1.-3I2

1.91

1912 - 11-t
R.I. 4168.

tPI¶IX^AMPLING 3 i

Cai ..-e. ... .' - t, .m..i 1y.',,r they- Cha + .~saiples'were,:taken in a number of the pi

had been extended since originally- sgp)ed by t'eQFedva~ a agelQotmal Survey,

In other pitsj samples were taken of the most highly mineralized zones, and

resulting assays are not to be considered as representative of thfe grade of

the deposits. 2Twenty,-fiveipit samples were shipped for analysis'and are recorded in table 8. Figure 4 shows the'location o6' these samples.'

TABLE 8. Pit samples disseminated sulfide demosit

Sample. j apPit h. ft. N yi . C , ' Remarks

a 8j 5.0 !0.20 o8

b 8...,*, 8 5.0 i.-24 .09 ,

c.. .. 8 5,0 i .33 .15

d .. . 8 5.0 -46 .21

e , 8 - . i .50 .33 .011

25.0 ' 1.56 0.54 Total

8 @ , -1i;0-#"25.O ,-:l- '. .312 .1081 Average table 2

10 5.0 . -.55 .006 1

10.0 0.72' 0,12 I

100 - i 360 1, .0601 Average table 2

.... @w..t 12 i ,0 .01 i .03 T

m ,,,,, 12 ! i0 5, ; Q- g05~Bi oa

-10: 0.08 0,0 ol

10.0 .040 | 0401 Average table 2

if ..... ,';.'' :23 ' *' 0 32:' I .12 - g ,.,,,,, . , 23 5.0 .38 10

i. .... 2 20 .0 0 57,0 6, .17.

n ........ * 5 5.0 .62 17 *33

o .,.......w... 5 5.b .69 .40

p5 q *K . -- .5 5.9 5.0 i .12 1 ,0, 405 P 5 5 :12 .2-~~~~05

y x .0**. , ! '5 3 5.0 bo O- i , ,, , v . 052 29 i- 059 i

s ! 35 ....... - . i ;. - e09 r 37'-I ,0-.3 .2

3 K 5,o0 Kl.18.6 t . +.. 35 5.0 .56

2 44 i' '09 41 

50 1.2 t ..8

1912 -. .

1912 -2
R.I. 4168

BIBLIOGRAPHY

Pecora, 1"Tilliam T., Nickel-Copper Deposfts on the Nest Coast of Chichagof

Island? Alaska: U. S. Geol. Survey Bull. 936-I, 1942, pp., 221-243.

Kenmedy, George C., and Walton, Matt S., Jr,, Nickel Investigations in

Southeastern Alaska: U. S. Geol. Survey Bull. 947-C, 1943 and

1944, p. 39-64.

1912 -13-