INVESTIGATIONS OF THE WHITE

MOUNTAIN MERCURY DEPOSIT,

KUSKOKWIM RIVER BASIN, ALASKA

By Raymond P. Maloney

report of investigations 6892

UNITED STATES DEPARTMENT OF THE INTERIOR

Stewart L. Udall, Secretary

BUREAU OF MINES

Walter R. Hibbard, Jr., Director
CL|T90ZZ9 Z689 'Ou LflCZNI

(SQ!J3S) -)1SeIV 'UTS~g JQATd WTu3ato3fSnX 'lTsodap AJnj

.jauw upezuno" azitq :apTl -II api1, -1 *ejsujV-sajo Ainiaia 1

*AqdrjIoTiqlq sapnloul

(Z689 suo!30

SQAUT Jo 3iodaj ssauIJ JO nuaing S rn) *sajqm "-snll! *d V6

[L9611 sauiyq lo nDaing 'lIoljaluI aj lo

daq s nfl [UO15UTSDMI D)ISDIV 'UTSDg laA!jj mIM3jOt¶SIl

'llsodap AinDIawu UTDjunofq a4lTM ap; lo SUOxlDbl4SaAUj

d puouixea 'Xiauo[1E

:sMollol so pagoloeoe uaaq seq uoileoilqnd siqi

A
CONTENTS

Page

Abstract ................. ,,,.....,, .,,....,,..........,,, .. I

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

Acknowledgments ......... . ...... .... ........... . ........... .. ........... * 2

History and ownership ... ...... .. .................... ........... ...... 2

Location and accessibility... .0 ...... ............. ...... ...... . ........ 2

Physical features and climate........... . ...................... ..... .... 5

General geology........................ . ........... . ...... . .. 6

Description of the deposits..... ........................................ 9

Work by the Bureau of Mines... ................... ........................ 30

Transportation... ...... 0.....0................ .................... . 30

Augering......... .,,,. ....... 0.... .............. ,.............. ..... 31

Explosives..A.--Log of t e........................................... 32

Trenchingn...........P o... f........................................ 32

Core drilling ..................,.................................... 33

Stream sampling ............ 0 O..................0...... .... ....... 33

Geophysical.... ... .,, *0 ............. ,................... 0..... O.. 33

Bibliography ......0... 0,..0.0.00...,.*....,... ...... .............. ...... 35

Appendix A.--Logs of trenches.......,,......O-#........,................. ... 36

Appendix B.--Petrographic analyses of trench sampe m p l es........ 56

Appendix C.--Logs of diamond-drill holes . . .63

Appendix D.--Assays and drilling data on diamond-drill holes ... 85

Appendix E.--Petrographic analyses of diamond-drill cores . . .............. 92

ILLUSTRATIONS

Fig.

1. Index and location map, White Mountain, A laska . . 3

2. Location and figure index map, White Mountain, Alaska. 4

3. Pan concentrate samples and cinnabar outcrops, White Mountain,

Alaska ........................................................... 7

4. Index of trenching maps ......... ....................... .. 12

5. Plan of trenches and diamond-drill holes, South and Central Zones.. 13

6. Plan of trenches south of South Zone, . .... 14

7. Plan of trenches and diamond-drill holes, Brown Bear Zone and north 15

8. Plan of South Z o ....... n e .................. ,., 17

9, Plan of Central Zone . ......... .............................. 21

10. Section on line AA, Central Zone ................................... 22

11. Section on line BB, Central Zone ................................... 23

12. Plan of Brown Bear Zone ...... .. .................... .27

13. Section on line CC, Brown Bear Zone . .......... 28

14. Section on line DD, Brown Bear Zone ............... ................. 28

15. Location of stream concentrate samples .................. .......... # 34
TABLES

Page

1. Petrographic analyses, conglomerate and granitics ................... 8

2. Spectrographic analyses of type samples ............................ 9

3. Petrographic analyses of Coxcomb, Ship Rock, Pump, and Sulfide

Springs samples... .. . .0 ....... .... ................ .. 0........... 10

4. Chemical analyses of Coxcomb, Ship Rock, Pump, and Sulfide Springs

samples,.... ,....... -........,..,... -- ...... ,,,,,,, 11

5. Spectroscopic analyses of stream pan concentrates,. ,,,,,,,,,,,,,, 16

6. Chemical analyses of stream pan concentrates ..................... 18

7. Chemical analyses of South Zone samples ............................ , 18

8. Chemical analyses of South Zone grid samples,.,,,,,,,,. ..,,,,,,,, 19

9. Chemical analyses of Central Zone grid samples.... ........... 24

10. Petrographic analyses of Central Zone samples...,,,,,,.,,.... 25

11. Channel samples in trench 11.... .. . .. .. ......... ... .. . ........ 26

12. Petrographic analyses of Brown Bear Zone sam ples . , 29

13. Chemical analyses of Brown Bear Zone grid samples . . 30
INVESTIGATIONS OF THE WHITE MOUNTAIN MERCURY DEPOSIT,

KUSKOKWIM RIVER BASIN, ALASKA

by

Raymond P. Maloney

ABSTRACT

The Bureau of Mines investigated the White Mountain mercury deposit, in

the Kuskokwim River Basin, to better determine the extent of mercury mineralization and to encourage its development by private industry. A program of

diamond drilling, augering, bulldozer trenching, and sampling was carried on

during four field seasons, from 1960 to 1963, inclusive. Significant amounts

of cinnabar, with only trace amounts of arsenic and antimony, occur in dolomite over an area about 4,000 feet long and 1,500 feet wide. The deposit

differs from other mercury deposits in the Kuskokwim River Basin by the

absence of silica-carbonate and rhyolite intrusives. Small-scale mining was

started in 1963 as the result of Bureau investigation and continued during the

summers of 1964 and 1965. The investigations indicate that open pit mining

might be the most feasible method of working this deposit.

INTRODUCTION

The mercury deposit at White Mountain, 65 airline miles southeast of

McGrath and adjacent to the Farewell Fault, was first examined by the Bureau

of Mines in 1958, and field investigations were carried on during the 1960-63

field seasons as part of the Department of the Interior program for the development of Alaska's resources. Owing to the remote location, lack of previous

investigations, and scarcity of placer gold, the area has seldom been prospected. The deposit was discovered in 1958 as a result of a deliberate search

for mercury by prospectors and engineers familiar with mercury prospects; some

preliminary hand trenching was done at the time of discovery. The Bureau did

augering, bulldozer trenching, diamond-core drilling, and sampling. Data

resulting from this investigation are presented in detail in this report.

1Mine examination and exploration engineer, Area VIII Mineral Resource Office,

Bureau of Mines, Juneau, Alaska.

Work completed on manuscript February 1966.
2

ACKNOWLEDGMENTS

Acknowledgment is made to Robert Lyman of Red Devil, Alaska, Ed Hager of

Cordero Mining Co., Palo Alto, Calif., C. L. Sainsbury of the Geological

Survey, Jack Egnaty of Sleetmute, and the Alaska Division of Mines and Minerals for information on the property; to the U.S. Air Force, the Alaska Air

National Guard, the U.S. Fish and Wildlife Service, and the U.S. Bureau of

Land Management for their help in transporting equipment and explosives; and

to the U.S. Army Corps of Engineers and U.S. Army for assistance in obtaining

shaped charges, and to the U.S. Bureau of Reclamation, the Federal Aviation

Agency (FAA), the Arctic Health Research Center, The Alaska Railroad, the U.S.

Bureau of Public Roads, and the General Services Administration for aid in

obtaining equipment and supplies.

HISTORY AND OWNERSHIP

Eskimo folklore spoke of a hunter who had seen some heavy red rocks on

a hill near the headwaters of the Tatlawitsuk River. Increased interest in

mercury encouraged a descendant of the hunter to investigate this folk tale.

In the summer of 1958, Jack Egnaty from Sleetmute found cinnabar float near a

large limestone hill which he called White Mountain. Seven lode claims were

staked by Egnaty and were leased to Cordero Mining Co. of Palo Alto, Calif.

Numerous other claims have since been staked by various parties. A number of

hand-dug trenches were excavated in 1958; most were only several feet in

depth, but one reached a maximum depth of 12 feet. In the fall of 1958, a

Bureau of Mines engineer made a reconnaissance of the property. In 1958-59,

the Geological Survey examined and mapped the mineralized area, and late in

the fall of 1959 a Bureau engineer examined it again. A Bureau party spent

the 1960 field season at White Mountain, and in the spring of 1961 the Bureau

moved tractors and a drill to the prospect from Farewell. The field seasons

of 1961, 1962, and 1963 were spent sampling the White Mountain deposits with

this equipment; in the early spring of 1964 all Bureau equipment was moved to

McGrath. In the summers of 1963 to 1965, the White Mountain property was

mined by Robert Lyman, who open pitted a small area.

LOCATION AND ACCESSIBILITY

The White Mountain mercury deposit is in the Kuskokwim River region,

McGrath district, McGrath subdistrict, at latitude 62010' N and longitude

154052' W (figs. 1-2). It is approximately 65 airline miles southeast of

McGrath between the headwaters of the Tatlawiksuk River and the Cheeneetnuk

River (tributary of Swift River); it is 4 miles west of Big River (also called

the West Fork of the Kuskokwim River). There are no roads or trails in this

uninhabited, isolated, and barren area. A small boat could, with difficulty,

go up Big River as far as the prospect. Natives are reported to have gone up

the Cheeneetnuk River by small boat to within about 15 miles of White Mountain

during high water. The Tatlawiksuk River does not appear to be navigable for

more than 20 miles from its mouth.

A 2,600-foot airstrip suitable for small, light planes was cleared by the

Bureau at the prospect. Large multiengine planes can operate from McGrath,
o 50 10/Nenana'

Scale, miles

LASK ro~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~40 N

antishna

MOUNT Mc KINLE

FIGURE 1. - Index and Location Map, White Mountain, Alaska.

CO~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~C,
an < arl LEGEND

Z) X t 0Sample .b9 location

Ci~~~~~~~~~~~ IS~~~~~~~ 15'0 ~ ~ ~~~~~~~~~~~~~~~~~~ 15430 15400 20D3

FIGURE 2. and - Lcation Fgure Index Ma, WhiteMounarewel Alanding
5

Farewell (an FAA station 45 airline miles northeast of the deposit), and from

the Red Devil field about 85 airline miles southwest of White Mountain.

Tractor trails suitable only for winter freighting by crawler-type tractors were pioneered by the Bureau from Farewell to White Mountain, a distance

of about 60 miles, and from White Mountain to McGrath, a distance of about 100

miles. Both routes have been traveled only once and leave much to be desired.

The best overland route to river barge service would be between the Selatna

River and the Little Selatna River to the Kuskokwim River, a distance of about

30 miles. River barges maintain a regular schedule on the Kuskokwim River

from about late May to October.

PHYSICAL FEATURES AND CLIMATE

The White Mountain deposit is at the extreme north end of an isolated

group of hills which extends southward for about 20 miles and has a maximum

width of about 15 miles. The highest and most prominent peak is White Mountain, a barren summit which rises to an altitude of 3,435 feet. The mercury

occurrences, adjacent to the mountain, range in altitude from about 1,600 to

2,200 feet.

The foothills of the Alaska Range are across Big River and less than 10

miles to the east where numerous peaks over 5,000 feet in altitude are covered

with snow most of the year. The terrain to the north and west consists principally of low rolling moss-covered hills and poorly drained flats covered

with spruce and brush interspersed with numerous open meadows and small lakes.

Vegetation is sparse. The numerous sharp peaks and ridges are usually

barren; the rest of the area is covered by residual rock and glacial gravels

of varying thickness overlain by a mantle of moss. Brush and spruce trees up

to 18 inches in diameter are found in creek valleys. The trees are usually 35

feet or less in height, scrawny, taper rapidly, and are poor lumber material.

The general appearance of the area is one of desolation and remoteness.

Animal life consists of a few stray caribou and moose, an occasional

grizzly bear, wolverine, porcupine, weasel, and martin. Parka squirrels and

beaver are more numerous. Wolves came within 100 feet of the camp. Grouse,

both spruce and ptarmigan, are present in small numbers. A species of migratory plover uses the area as a summer nesting ground. Ravens, a few small

hawks, and an occasional bald eagle are seen. The streams contain a few grayling, usually less than 4 inches long..

Winters are long and cold and the summers short and comparatively warm.

Temperatures range from about 90° F to probably more than -50° F with an average temperature of about 450 F during the warm summer months of June to

September. Frost and snow occurred every month from May to September during

the four years the Bureau worked here. The greatest snowfall during the four

field seasons occurred on July 1, 1963, when 3 inches fell. Fog and rain are

frequent with the annual precipitation estimated at about 20 inches or less.

Winds up to an estimated 70 knots or more are common. Permafrost and ice

lenses are encountered in most of the area.
6

GENERAL GEOLOGY

Detailed geology of this region is not available. A. T. Fernald of the

Geological Survey has described the surficial deposits on a reconnaissance

basis but has classified most of the bedrock as unsurveyed (2).2 C.L. Sainsbury

and E. M. MacKevett of the Geological Survey examined the deposit at White

Mountain and made available to the Bureau the use of their detailed geologic

map of the deposit area (4), and gave valuable advice on the location of

trenches and drillholes. Other general features are described in the Geological Survey publications listed in the bibliography. The following brief discussions of the general geology are based on data from the above sources and

from examinations and observations of the writer.

The group of unnamed dolomitic limestone and shale hills including White

Mountain are part of the Kuskokwim uplands which rise out of a piedmont plain

originating in the Alaska Range. Lone Mountain, made up of dolomitic limestone and shale, and the shale and conglomerate hills along the Selatna River

are also part of these uplands. The limestone and shale at White Mountain are

probably Paleozoic, and the conglomerate Cretaceous (4). The limestone and

shale formations at Lone Mountain and the conglomerate forming the ridges at

the head of the Selatna River appear to be similar to those at White Mountain.

The piedmont plain, covered with moraines, alluvial fans, and flood

plains, extends northwestward from the Alaska Range to about Lone Mountain.

From here to the Kuskokwim River there are swampy, poorly drained lowlands,

shallow lakes, and numerous sand dunes. Big River, the largest stream,

changes from a braided to a meandering type after it flows past Lone Mountain.

Other streams are small and sluggish. Most of the area, including the deposit,

has been glaciated (3), but the evidence is subdued.

There are three prominent geologic features in the immediate vicinity of

the deposit; White Mountain, the Farewell Fault, and a tilted conglomerate

formation (fig. 3). White Mountain, a massive dolomite limestone that can be

seen from the air for 50 miles, is part of the Paleozoic shale and limestone

formation which is host to the mercury mineralization. The Farewell Fault, a

major regional fault, separates the limestone and shale beds from the conglomerate formation. The dip of this fault is probably almost vertical and evidence indicates that it has been active in recent times. The Cretaceous

conglomerate formation on the east side of the Farewell Fault dips to the

northeast. It is composed mainly of well rounded quartz and shale fragments

up to one-fourth of an inch in size, well cemented, and is a very dark gray

color when freshly broken; it weathers to a medium gray gravel. Significant

mercury mineralization was not found in this formation. Petrographic analyses

of type samples are in table 1; a spectrographic analysis of a conglomerate

type sample (45-8) is in table 2.

2 Underlined numbers in parentheses refer to items in the bibliography at the

end of this report.
7

t : = :y/y~~~~

at:ES C::TL: :0gt~~~~~~~~~~~

X~~~~~~~~~~~ = 44 

9 3200 4000 60

FIGURE~~~~~~~~~~~~~~~~~~~11 - a 24 ocnrt ape n inbrOtrpWieMutilsa
00

TABLE 1. - Petrographic analyses, conglomerate and granitics

Sample

45-8 45A-8 46-8 46A-8 46B-8 46C-8 46D-8 15-0 509-0 513-0 514-0 108-3 110-3

Sample description' ....... 1 1 1 1 1 1 1 2 1 2 1 2 1

Rock classification:

Conglomerate ............ C - - C - - - C

Diorite ................. C _ _ _ _ _ _ 

Granodiorite ............ C _ _ C _ _ _ _ _ 

Granite ................. C C C C C

Sandstone ............... - - C C C -

Mineral:

Albite .................. - - - S A S _ P - _ _ S _

Andesine ................ - - - - A

Apatite ................. - - - - T

Biotite ................. - - - M M M S _ _ S

Carbon .................. F - - - M

Chlorite ................ A - - - _ M _ M S F S _ _ 

Fluorite ................ - - - - T F S

Goethite ................ - - - - F

Hematite ................ - T - - T

Hornblende . ..- - - _ M A _ T _ M _

Illite .................. A - A - P _ A _ _ 

Limonite ................ F T M F F _ T M - _ F _ F

Magnetite ............... M M T -_ _ _ _ 

Microcline .............. _ - - P _ _ _ 

Oligoclase .............. - - A - - A _ _ _ 

Orthoclase .............. _ P M A S A T A - _ A -

Quartz .................. P S A S S S T A S A P A P

P--Predominant ................ Over 50 percent.

A--Abundant ................... 10 - 50 percent.

S--Subordinate ................ 2 - 10 percent.

M--Minor ..................... 0.5 - 2 percent.

F--Few ...................... 0.1 - 0.5 percent.

T--Trace ................ Less than 0.1 percent.

C--Rock classification.

1 1--Conglomerate. 2--Granitic north of deposit.
9

TABLE 2. - Spectrographic analyses of type samples

Sample =

6-8 7-8 8-8 12-8 15-8 43-8 45-8

Sample description............. 6 2 3 4 7 5 1

Element:

Aluminum ...................... C C D D D C C

Arsenic ....................... _ D _ D _

Barium ........................ E E

Beryllium ..................... G G

Boron ......................... D D F F _ F F

Calcium ....................... D D A A A A E

Chromium ...................... E E F F F E E

Cobalt ........................ F

Copper ........................ G G G G G G F

Iron .......................... C A D C D D D

Magnesium ..................... D D B A B D D

Manganese ..................... F F F E F E F

Mercury ....................... E E A E D A D

Molybdenum .................... F F

Nickel ........................ F F F F F _ E

Silicon ....................... A A D D E C A

Sodium ........................ D D E E E _ D

Tin ........................... E D

Titanium ...................... C C F F F E E

Vanadium ...................... D D E D E E E

Zirconium ..................... E E F

A--Over 10 percent. E--O.O1 to 0.1 percent.

B--5 to 10 percent. F--0.OO1 to 0.01 percent.

C--l to 5 percent. G--Under 0.001 percent.

D--0.1 to 1 percent.

1l--Conglomerate. 2--Fault gouge, South Zone (7-8). 3--High-grade cinnabar

mineralization, South Zone (8-8). 4--Barren gray dolomite, South Zone

(12-8). 5--High-grade cinnabar, Ship Rock. 6--Fault, Brown Bear Zone.

7--Dolomite with cinnabar in fractures, South Zone (15-8).

Granitic outcrops occur about halfway between the north end of the

deposit and Big River. Petrographic analyses of type samples are in table 1.

Granitic intrusives are also present about 2 miles downstream from the south

end of the deposit adjacent to the north bank of the Cheeneetnuk River.

Mercury mineralization was not found in any of these intrusives.

DESCRIPTION OF THE DEPOSITS

Between the west side of the Farewell Fault and White Mountain, cinnabar

occurs in dolomite and limestone in an area about 12,000 feet long and 1,500

feet wide (fig. 3). This formation is composed of bedded shale, limestone,

and dolomite; bedding planes strike N 30° E and dip about 85° E. Faulting is

extensive and essentially parallel to the bedding planes.
10

Cinnabar is the mercury-bearing mineral, but unlike other cinnabar deposits in the Kuskokwim River Basin, antimony and arsenic are absent or only

occasionally present in trace amounts. This deposit also differs from other

deposits in the absence of altered silica-carbonate and rhyolite. Altered

volcanic material or trachyte was found in several trenches and drillholes,

but it did not appear to be associated with mercury mineralization. Petrographic analyses indicate that some of the steep faults were mineralization

channels but the best of the cinnabar zones are probably of hydrothermal

origin in a brecciated, silicified dolomite. Cinnabar was found in limestone

in minor amounts; it was not found in shale.

A conspicuous exposure herein called the Coxcomb outcrop occupies the

south end of this 12,000-foot-long mineralized area (fig. 3). This outcrop,

about 10 feet long and 4 feet wide, is at the top of a sharp barren limestone

ridge on the east bank of the Cheeneetnuk River. Here, a few small, short

stringers of cinnabar occur in a black and gray limestone which is cut by

numerous small stringers of calcite. Petrographic analyses of type samples

(512-0, 488-0, and 88-3) of the outcrop are in table 3.

TABLE 3. - Petrographic analyses of Coxcomb, Ship Rock,

Pump, and Sulfide Springs samples

Samle

1-1 84-3 86-3 488-0 512-0 88-3 89-3 90-3 516-0 106-3

Sample description1..... 1 1 2 2 2 2 2 3 4

Rock classification:

Dolomite .............. C

Limestone ............. C C C C C C C C _ _ 

Mud ................... C

Mineral:

Calcite ............... P A P P P P P P - A

Chlorite .............. - - M - M M S S S -

Cinnabar .............. M P S S _ S S A T A

Dolomite .............. - - - - - M M P

Goethite .............. - - - - - T

Illite ................ - - M - - M S S M _

Limonite .............. T M - T

Quartz ................ - M P

P--Predominant . .......... Over 50 percent.

A--Abundant . ........... 10 - 50 percent.

S--Subordinate . ......... 2 - 10 percent.

M--Minor . ............ 0.5 - 2 percent.

T--Trace ............... Less than 0.1 percent.

C--Rock classification.

1--Ship Rock. 2--Coxcomb to Ship Rock. 3--Sulfide Springs. 4--Pump.

Two stringers of cinnabar, each 2 feet long, 1/2 inch wide, and 50 feet

apart, are in black limestone with calcite stringers about 3,600 feet north of

the Coxcomb and on the same side of the Cheeneetnuk River. A petrographic

analysis of a type sample (89-3) is in table 3. Approximately 900 feet further upstream, or north from this point, a few very small stringers of
11

cinnabar occur in similar limestone. A petrographic analysis of a type sample

(90-3) is found in table 3.

The largest showing of mercury mineralization on the east side of the

Cheeneetnuk River and adjacent to the Farewell Fault is called the Ship Rock

outcrop; it is about 500 feet north of the last-mentioned outcrop, or 5,000

feet north of the Coxcomb (fig. 3), and is in the same black-gray limestone in

which the three previously mentioned outcrops occur. Blocks of limestone as

much as 10 by 10 feet in size lie at the base of a cliff 50 feet high and 200

feet long. Small stringers and lenses of cinnabar occur in these blocks and a

few lenses of cinnabar can be seen in the face of the cliff. The largest lens

is 4 by 12 inches. None are over 1/2-inch thick. Blasting with dynamite and

shaped charges created a fresh face on the cliff and exposed other lenses of

cinnabar, but mercury mineralization was irregular and minor. Considerable

calcite is present.

Petrographic study of specimens from this area indicated that the limestone was first cut by calcite veins; later, cinnabar and more calcite were

deposited. Traces of orpiment and realgar accompanied the introduction of

cinnabar. Additional calcite veins then cut the cinnabar and the previously

formed calcite deposits. Petrographic analyses of type samples from the Ship

Rock outcrop are in table 3; chemical analyses of high-grade samples are in

table 4.

TABLE 4. - Chemical analyses of Coxcomb, Ship Rock, Pump,

and Sulfide Springs samples

Sample Description Percent

Mercurv Antimony Arsenic

43-8 Stringers of cinnabar in black limestone 24.9 0.3 0.1

at Ship Rock.

1-1 High-grade specimen at Ship Rock .4.58 - -

2-1 Gossan near Sulfide Springs .04 - -

85-3 High-grade specimen of cinnabar and 66.8 - -

limestone at Ship Rock.

87-3 Cinnabar and limestone at Ship Rock .6.24 - -

107-3 . do .28.58 - -

105-3 Very similar to 106-3, Pump Zone .......... 9.12 - -

516-0 Sulfide Springs mud ....................... .03 .07 .02

526-0 Sulfide Springs water (ppm, negative <.02 <.02 .30

tellurium and selenium).

About 500 feet north, or upstream, from the Coxcomb and on the east side

of the Cheeneetnuk River there is a hydrogen sulfide spring. Petrographic

analyses of samples of the mud are in table 3, and chemical analyses of mud

and water in table 4. These indicate that cinnabar is being deposited by this

spring. Between this spring and the Ship Rock outcrop there are several other

clear water springs; all originate on the east or Farewell Fault side of the

Cheeneetnuk River.
12

i \0° O) |o ) ) ( The most mineralized seeR n O iv r / tion in this area is on the

0 ' Iso FIGURE / °0 7 west side of the Cheeneetnuk

0 t~o River. ° \ This t V is X where o Ace/<> most of

the Bureau work was done,

including all of the trenching

X / //and diamond drilling (figs.

4-7). The description of

A ( i i J; 7 / y / /deposits in this section will

F IG6 U ~RE/ 5 / a t start from the south end with

trench 52 (fig. 6) and con-

_ ,~ )Xtinue on north.

Pan concentrates in the

vicinity of trench 52 indicated that cinnabar was pres0o l ent, / / but w trenching X n J Go 4 \disclosed

co /l lit a trace X / amount p i > \<>vuZonly in bed1 I rock. 1/ \ The locations of these

concentrate samples are shown

/ FIGURE" 6 , BAJA / < \ H a on figure 3; spectrographic

and chemical analyses are in

tables 5 and 6.

Between trench 52 and

trench 30, bedrock is covered

0 o 9 with 4 , o vegetation and overburden.

All drainage courses were

2000 4000 panned and 3,000 linear feet

/!!!6iiiiii ,eof bedrock were exposed in a

tractor road. No mercury minFIGURE 4.- Index of Trenching Maps. eralization was found.

The most important and greatest amount of mercury mineralization at the

White Mountain deposit is found along a 4,000-foot length of the ridge between

trench 30 and trench 33 (figs. 5, 7). All of the diamond drilling and most of

the trenching was done here. Logs and assays of this drilling and trenching

are in appendixes A-E. All mineralization was in a silicified gray dolomite

or altered hydrothermal rock closely associated with the silicified dolomite.

The South Zone was one of the two original discoveries at White Mountain,

the other being the Brown Bear Zone about 3,600 feet north. Figure 8 shows

the location of diamond-drill hole 14 and channel samples in the South Zone.

Tables 7 and 8 give chemical analyses of samples and table 2 spectrographic

analyses of a few type samples.

When the South Zone was first discovered, high-grade cinnabar float was

present. Trenches dug in 1958 by hand methods showed considerable cinnabar

in a brecciated yellow and gray weathered dolomite zone about 100 feet long

and 40 feet wide. The maximum depth of these trenches was 12 feet; mineralization at this depth was much less than near the surface. Cinnabar was
13

1 1.000 N

LEGEND

C.:t-: Bulldozer trench

3o Diamond-drill hole

Cimnonabar (HgS)

Altered volcanic

Fault

85- Strike and dip ot beds

Sculm.le n IOONs /X7

0 00N 200 300 4000 7~~~~~~~~~~~~~~~~1

FIGURE 5.8PlanofTrenchesandDiamond-DrillHolesSouthandCe 8 9000N tN/) Zone

a1 OOONOO

FIGURE 5. -Plan of Trenches and Diamond-Drill Holes, South and Central Zones.
14

LEGEND

Bulldozer trench

0~~~~~~~~~~~~~~~~10

0~~~~~~~~

0(0~~~~~ 51 V 1 /e

/ ~~~0 100 200 300 400 500

Scale, feet

FIGURE 6. - Plan of Trenches South of South Zone.
15

LEGEND

44 -- 44 Bulldozer trench

013 Diamond-drill hole

2460

13,)OON

2~~~~~~~~~~~~~~~20

cz::zzzz~~~~~~~~~~~~~~~~~~~~~~~ E ~~13,000 

0 100 200 300 400 500

12000 E / \ / /Scale, feet

FIGURE 7. - Plan of Trenches and Diamond-Drill Holes, Brown Bear Zone and North.

present as small veins, small lenses, and fracture fillings. The dolomite was

cut by veins of dolomite and cinnabar, the vein dolomite being the first

introduced. In some instances, crystals of cinnabar had replaced dolomite

with no channels of introduction visible. A brownish spherulitic crust of

calcite was often present. Minor limonite and quartz were present, but only

traces of stibnite and realgar.
TABLE 5. - Spectroscopic analyses of stream pan concentrates

Element Samplel

1m2t3 4 c 8 _56 910 11 12 13 1415 16 17 18119120 21 22123 24 25126 27 28 29130131 32 33134 35

Copper --------------------- --- - - --- T - -------

Mercury X X - - - - X T - - - - - - - - T - T T - - - _- - - - T _- - T - Silver--------------------- - --- --- - -- -- --- T -T

Titanium X X T X XX X T T X T T X X X X X T _- - X X T - - T T T T X X X X X

Yttrium ---- T------------------------------

Zinc -- T- - -T.

Zirconium T T T TT T T T T T T T T T - T - - - - T T _ _ T T T - T T T T - T

Saml el - -

36 37 38 39 40 4142 434445 4647 4849 50 51 52 53 54555657 5859 6061626364656667

Copper - - ------------- T----------------

Mercury T - T-X -T -X - - TX X -T - - XT - - T- - - TX -

Silver T T -T - - - - - - - - - - - - - - - - - - - - - - - -

Titanium X X X X X X X X T T T T T T T T T X T T T - - T X T T T T T T T

Yttrium - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Zinc - T - T T T - - - - - T T- - T T X T T T- -T - T - T T T - T

Zirconium T| T T T T T T T T T T T T T - - -T-- T - - - - - T -

- - - ~~~~Sample1

68 69 70 71 72 73 74 75 76 177 78 79 180181 82 83 84 185 86 87188 89 90 91192 93146A 147A 48A 58AI65A

Copper -- - - - - - - - - - - - - - -| -| - - - - - - - | T - T

Mercury T X X T X T - T - - X T X T X X X X X X X X X X X X X T - - - Silver - - -----------------------------

Titanium X X X T T X T X T T X X T T T T T T T T T - T T T - T T T T T

Yttrium - - -----------------------------

Zinc T T T T - T T - -| T T -| T| T T T T|T T TT T T T T| T -| IT | T - -

Zirconiuml 1- 1- 1-- T --

X--Detected in sample. T--Trace, less than 0.1 percent.

1 Location in figures 3 and 15.

Note: Samples were taken in 1963
17

LEGEND -

Dolomite \ %1|lX Shale

\ Limy shale

| Dolomite

* s2 549|4g 5 4443 ' 41 4_ Siltstone

nO.49

48,47 4845.. ,1 -Channel sample

DDH-O 14Diamond-drill hole

* a Bedr~~~~~~ock exposed bybuloe Fault

NOTE: When referring to tables,

4 3 z \ * Q ,,,all samples on this map

\~~~~~~~~~~~ 50l 4e to ,6 e n i|, n, 19 639 tha Is '- 3 - o'63

DDH-14- - t

Discovery post 7

3433 31_3os29 3 8127 ,Z -

Dolomite

0 20 40 60

S l. Is\f.et

FIGURE 8.- Plan of South Zone.
18

TABLE 6. - Chemical analyses of stream pan concentrates1

Sample Percent mercury

1...................................... 0.02

2 ...................................... .02

43 ...................................... .01

47 ...................................... .02

69 ...................................... .01

72 ...................................... <.01

80 ...................................... <.01

82 ...................................... .05

83 ...................................... 1.45

84 ...................................... 7.08

85 ...................................... .08

86 ...................................... .57

87 ...................................... .31

88 ...................................... 4.15

89 ...................................... 63.7

90 ...................................... 1.29

91 ...................................... <.1

92 ...................................... .03

94 ...................................... .02

46A ..................................... .01

Location shown in figures 3 and 15.

TABLE 7. - Chemical analyses of South Zone samples

Sample Description Percent Ounce per ton

Mercury Antimony Arsenic Gold Silver

17-8 Fault gouge ................ 0.1 Trace Trace Trace Trace

18-8 Specimen of cinnabar and 10.5 Trace Trace Trace Trace

yellow dolomite.

9-8 Specimen of cinnabar and 10.0 Trace Trace Trace Trace

gray dolomite.

10-8 Barren gray dolomite ....... .05 Trace 0.05 Trace Trace

11-8 Specimen of mineralized 7.4 Trace .11 Trace Trace

yellow dolomite.

112-8 Brown, decomposed dolomite, .3 Trace .1 Trace Trace

limonite stain.

13-8 Specimen of cinnabar and 3.1 Trace .9 Trace Trace

dolomite.

14-8 ........ do ............... 2.7 Trace .6 Trace Trace

115-8 . ...... do ............... 5.6 Trace .05 Trace Trace

44-8 ........ do .14.0 0.3 Trace Trace Trace

1 See table 2 for spectrographic analyses.

In 1962 this zone was bulldozed to a depth of 3 to 4 feet. All evidences

of the hand-dug trenches were removed or destroyed. Most of the visual evidence of the mercury mineralization was also removed by this bulldozing,

although as shown by table 8 several good areas were still present. The

amount of limonite exposed increased as much as 50 percent. Diamond-drill
19

hole 14 was drilled through what was the best surface showing of cinnabar

(fig. 8). Logs and assays of this hole are in appendixes C and D. Results of

this drillhole were disappointing, but core and sludge recovery were poor.

Mineralization is probably better than indicated. Fracturing appeared to be

much less as depth increased. Assays of channel samples taken over this bulldozed area are in table 8.

TABLE 8. - Chemical analyses of South Zone grid samples

Samplel Line Interval, Width, Percent Samplel Line Interval, Width, Percent

feet feet mercury feet feet mercury

1 1 0- 5 5 0.32 29 2 40- 45 5 0.02

2 1 5- 10 5 4.74 30 2 45- 50 5 .02

3 1 10- 15 5 .55 31 2 50- 55 5 <.01

4 1 15- 20 5 .03 32 2 55- 60 5 .43

5 1 20- 25 5 .33 33 2 60- 65 5 <.01

6 1 25- 30 5 <.01 34 2 65- 70 5 .04

7 1 30- 35 5 .17 35 2 70- 75 5 .14

8 1 35- 40 5 .57 36 2 75- 80 5 <.01

9 1 40- 45 5 .02 37 2 80- 85 5 .02

10 1 45- 50 5 <.01 38 2 85- 90 5 .02

11 1 50- 55 5 <.01 39 2 90- 95 5 <.01

12 1 55- 60 5 <.01 40 2 95-100 5 .02

13 1 60- 65 5 .07 41 3 0- 5 5 .03

14 1 65- 70 5 <.01 42 3 5- 10 5 .15

15 1 70- 75 5 .03 43 3 10- 15 5 .03

16 1 75- 80 5 .03 44 3 15- 20 5 .12

17 1 80- 85 5 .02 45 3 20- 25 5 .08

18 1 85- 90 5 .02 46 3 25- 30 5 <.01

19 1 90- 95 5 .02 47 3 30- 35 5 <.01

20 1 95-100 5 .02 48 3 35- 40 5 <.01

21 2 0- 5 5 .05 49 3 40- 45 5 <.01

22 2 5- 10 5 .10 50 3 45- 50 5 <.01

23 2 10- 15 5 .05 51 3 50- 55 5 <.01

24 2 15- 20 5 .05 52 3 55- 60 5 <.01

25 2 20- 25 5 .04 53 3 60- 65 5 .01

26 2 25- 30 5 .01 54 3 65- 70 5 .01

27 2 30- 35 5 <.01 55 3 70- 75 5 <.01

28 2 35- 40 5 <.01 56 3 75- 80 5 <.01

1 See figure 8 for location of samples.

A fault separates the shale and dolomite at the South Zone (fig. 8). The

material in this fault is composed of illite-derived from altered feldspar.

Some bentonite clay is present and a trace of carbonate. A similar fault is

present at the Brown Bear Zone, but spectroscopically more iron and less magnesium were present in the samples from the South Zone fault. Petrographic

studies of samples from this fault and from several of the numerous other

faults in the area (including the one at the Brown Bear Zone) suggest that

some of the samples may be clay residues of old mineralization channels rather

than fault gouge. Spectrographic analyses of samples of the South Zone and

Brown Bear Zone faults are in table 2.
20

Diamond-drill hole 14 penetrated, from 142.0 to 147.4 feet, a highly

altered rock. This appears to be the same altered material as found in

trenches 7, 13, 20, 21, and 30 and in drillholes 9, 10, and 12 at the Brown

Bear Zone. A study by Bureau petrographers determined that the material is

essentially a highly altered, fine-grained porphyritic igneous rock of hypabyssal origin with the general composition and characteristics of trachyte.

The highly altered condition of this rock precludes a more exacting classification; however, the abundance and mode of occurrence of secondary chlorite

and calcite suggest that the material might have been a basic igneous rock.

This cannot be considered entirely conclusive inasmuch as at least some of the

calcium and magnesium for formation of chlorite and calcite could have been

made available by the intruded dolomite or limestone.

Mineralogically, the rock consists of small, corroded or replaced, elongated feldspar phenocrysts in a fine-grained groundmass which has been altered

to chlorite, limonite, and calcite. Some of the calcite has replaced feldspar

phenocrysts; some has replaced original groundmass minerals or filled interstices and veinlets. Most of the feldspar that is not completely altered is

albite plagioclase. Laths are twinned, but the twinning planes are highly

irregular, suggesting deuteric recrystallization and replacement of the original feldspar. No pyroxenes or amphiboles were observed in thin section; they

either were not present originally or have been replaced subsequently by chlorite. Subject to these qualifications, the material is termed "trachyte" when

referred to in trench and diamond-drill hole logs.

Considerable trachyte was found in trench 30 (fig. 5) which is adjacent

to the south end of the South Zone. A 1-foot-wide mineralized zone over 30

feet long was found by bulldozing. It consisted of 3 to 12 inches of a white

claylike trachyte capping on top of 6 to 12 inches of soft brown disintegrated

dolomite which contained considerable fine granular cinnabar. In places, this

6 to 12 inches of dolomite below the trachyte contained over 60 percent mercury. Cinnabar mineralization appeared to end abruptly after a depth of 12

inches below the trachyte. The surrounding formation was a gray dolomite.

There was no halo or gradually fading of mercury mineralization into the surrounding gray dolomite; it ended abruptly at the edge of the trachyte. This

mineralized zone was still present when it entered the east wall of the

trench, but with much less mineralization. However, on strike with this zone

and about 500 feet further southwest a small lens of cinnabar was found in

dolomite in a steep cut bank. This would be about 40 feet vertically below

the zone in trench 30. Overburden in trench 30 was about 10 feet thick. No

sign of mineralization was on the surface. Trenching has removed all evidence

of mineralization in the trench and spoil from trenching has covered the small

lens of cinnabar in the cut bank. Assays of samples are found in appendix A

and petrographic analyses are in appendix B.

Minor occurrences of cinnabar were found in siliceous dolomite in a number of trenches between the South Zone (fig. 5) and the Brown Bear Zone (fig.

7). Chemical and spectroscopic analyses of samples of these occurrences are

in table 3 and appendixes A and B. One of the largest of these occurrences

was found in trench 23 and is called the Spring Zone (fig. 5). A spring flows

about 30 feet below this zone; there did not appear to be any association

between it and the mineralization.
21

gkrench 24

/ by bulldozer- \=

/ dolomite and limeston

/ rrotic HgS\

A DH-2 A

DDH-6DH8

LEGEND

Dolomite D5

* LZIJ ~~~Geyserite '731 Channel sampleTrcHg

OH -X Diamond-drill hale

NOTE :When referring to tables, all

samples on this map taken

in 1962; thatIs 67-2 to 117-2.

0 20 40 60

Scale, feet

FIGURE 9. - Plan of Central Zone.
22

Dolomite / I,

2100 ft elev Il

0~~~~~~~~~~~~~~~12E

0,~~~~~~~~~~~~~~~~

LEE 6

4~~~~~~~~~~~~~~~~

LEGE ND

2.7 Pounds of mercury

per ton

NOTE: All drillholes

projected to plane A-A

0 20 40

Scale, feet

FIGURE 10. - Section on Line AA, Central Zone.
23

The Central Zone (figs.

5, 9-11) contains the best

occurrences of cinnabar found

2100 X ft at the White Mountain deposit. elev \ ¢ If/< / ' / ' / ' ; The only surface indication

prior to work by the Bureau of

Mines was a few minor cinnabar

lenses exposed in a nearby

dolomite outcrop. A power

auger was used to outline a

highly mineralized zone or

pocket which is elliptically NOTE: Driliholes projcted shaped, having about a 50-foot

to plane B-S' \ major axis and a 30-foot minor

axis. Eight diamond-drill

holes (holes Nos. 1-8, fig.

LEGEND _ 10) were drilled in and around

this zone which was also chan- 2.2 Pounds of mercury nel sampled. Results are in

per ton tables 9 and 10 and appendixes

C-E.

0 20 40

Scale, feet AS Core recovery was poor in

some of these holes, but drill- FIGURE 11. - Section on Line BB, Central Zone. ing indicates that high-grade

mineralization extends to at

least 25 feet below the surface; subsequent open pit mining of this zone is

verifying this. Drill sludges indicate that cinnabar is present in lesser

amounts at 200 feet below the surface, the greatest depth that could be

drilled by a single shift operation because of difficult conditions encountered due to permafrost and coring broken formations. Much of the core was

vuggy; occasionally a small lens or bleb of cinnabar would still be attached

to a vug but could easily be broken off by hand.

Considerable geyserite occurs in the top 3 to 4 feet of the Central Zone

deposit and it usually contains cinnabar. Gray, siliceous dolomite is the

chief host rock. Drillhole 5 apparently penetrated a large cavern at 40 feet.

All water was immediately lost and a strong blast of odorless air blew from

this hole for 48 hours. In trench 11 about 100 feet southwest of the Central

Zohe (fig. 5) an erratic mineralized zone was exposed for about 80 feet. This

was channel sampled and the results are in table 11. Other analyses are found

in appendixes A and B.

A small deposit similar to the Central Zone was found by tracing cinnabar

float approximately 1,000 feet up the slope of a steep hill from the pump or

dam where drilling water was obtained. It was uncovered in trenches 17 and

17-A (fig. 5), and is called the Pump Zone. Cinnabar mineralization occurs in

a 5- by 20-foot area of dolomite which also contains several pockets of geyserite, each less than a foot in diameter. Overburden, 15 to 20 feet in depth,

covering this zone on a steep hillside, caused continued caving which made

trenching difficult and dangerous; only a limited amount of sampling could be

accomplished. Sampling results are given in appendix A.
24

TABLE 9. - Chemical analyses of Central Zone grid samples'

Sample2 Line Interval, Width, Percent Sample2 Line Interval, Width, Percent

feet feet mercury feet feet mercury

67 1 0-50 50 0.01 92 7 25-30 5 10.42

68 2 0-50 50 .04 93 7 30-35 5 8.12

69 3 0-50 50 .03 94 7 35-50 15 .43

70 4 0-14 14 .02 95 8 0- 7 7 1.05

71 4 14-15 1 .02 96 8 7-12 5 2.96

72 4 15-20 5 2.50 97 8 12-17 5 5.79

73 4 20-25 5 .39 98 8 17-22 5 12.60

74 4 25-30 5 7.94 99 8 22-28 6 4.67

75 4 30-33 3 13.32 100 8 28-32 4 .38

76 4 33-50 17 .10 101 8 32-36 4 .32

77 5 0-17 17 .01 102 8 36-40 4 7.04

78 5 17-20 3 5.34 103 8 40-44 4 .85

79 5 20-25 5 1.08 104 9 0-11 11 .84

80 5 25-30 5 2.94 105 9 11-15 4 4.77

81 5 30-35 5 1.11 106 9 15-20 5 2.34

82 5 35-40 5 .02 107 9 20-25 5 3.17

83 5 40-50 10 .20 108 9 25-30 5 1.06

84 6 0-20 20 .12 109 9 30-32 2 .10

85 6 20-25 5 4.61 110 9 32-50 18 1.07

86 6 25-30 5 2.67 111 10 0- 9 9 .20

87 6 30-33 3 5.50 112 10 9-15 6 1.41

88 6 33-50 17 .25 113 10 15-36 21 .07

89 7 0-15 15 .03 114 11 0- 8 8 .55

90 7 15-20 5 3.62 115 11 8-12 4 1.63

91 7 20-25 5 13.14 116 11 12-20 8 .12

_____ _ _ _ 117 (3) _ 2.04

'See table 10 for petrographic analyses.

2 See figure 9 for locations.

3Large grab sample.

Note: Samples were taken in 1963.

The Brown Bear Zone is at the north end of the White Mountain deposit,

and along with the Central Zone, is one of the two most important mercury

zones at White Mountain; figures 7 and 12-14 show locations of trenches and

drillholes in this zone. Chemical and petrographic analyses of type samples

in grid areas are in tables 12 and 13. Logs of trenches and drill holes are

in appendixes A-E. Table 2 gives a spectrographic analysis of a sample (6-8)

of a fault similar to that found in the South Zone (7-8).

At the Brown Bear Zone cinnabar occurs in a silicified dolomite in lenses,

blebs, and veins over an area about 20 by 70 feet. The original discovery was

a vein that was 6 to 12 inches wide and appeared to be over a hundred feet

long, as indicated by float. Trenching proved that most of this indicated

length was due to frost creep and that it was actually about 10 feet long and

6 feet deep. Mineralization was not found in the shale. Geyserite was not

present, but trachyte was found in diamond-drill holes. These drillholes indicated that mineralization was shallow and did not go to any such depth as at

the Central Zone; however, core and sludge recovery were poor and at the interval drilled short rich ore shoots can be straddled.
TABLE 10. - Petrographic analyses of Central Zone samples

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 4 _ 8 _ _ 5 -0 - 5 1 5 -0 a m p l e '

485-0 511-0 515-0 517-0 525-0 67-2 71-2 72-2 78-2 81-2 91-2 94-2 95-2 99-2 117-2 103-3

Rock classification:

Cinnabar ore ...... C C C C C - -_ _ _ _ _ _ _ _ _ 

Dolomite .......... - - _ C -

Limestone - _ _ _ -......... C _ _ _ _ 

Springs deposit ... - - _ C C C C C - C C C C

Mineral:

Calcite ........... - - S _ F T - T - N P N N _ _ 

Cinnabar .......... A A P A S T N S F F S T T A T M

Dolomite .......... P N _ _ - -

Limonite .......... M -_ _ _ _ _ _ _ -

Quartz ............ P _ A P P A P P P P P S P P P P

P--Predominant . .......... Over 50 percent.

A--Abundant . ............ 10 - 50 percent.

S--Subordinate . ........... 2 - 10 percent.

M--Minor . ............. 0.5 - 2 percent.

F--Few . ............. 0.1 - 0.5 percent.

T--Trace ............... Less than 0.1 percent.

C--Rock classification.

N--Sought but not detected.

'Locations are shown in figure 9.

Note: Samples 485, 511, 515, 517, 525, and 103 are specimen samples; no chemical assay.
26

TABLE 11. - Channel samples in trench 11

Samplel Interval in trench, Width, Percent

feet feet mercury

67-3 44- 52 8 <0.01

66-3 52- 59 7 .13

65-3 59- 65 6 <.01

64-3 65- 72 7 .10

63-3 72- 79 7 .48

62-3 79- 85 6 .01

61-3 85- 90 5 .02

60-3 90- 97 7 .01

59-3 97-104 7 <.01

58-3 104-110 6 .03

57-3 110-116 6 .03

56-3 116-122 6 .26

ISampled section shown in figure 5.

Trenches across the small stream north of the Brown Bear Zone (fig. 7)

did not reach bedrock, though some were over 16 feet deep. Frozen gravel and

boulders cover this area to an unknown depth. Pan concentrates and traces of

cinnabar in nearby dolomite outcrops indicated that cinnabar might be present

at this end of the White Mountain deposit.
27

D ~ ~ ~ ~ D-~--~DD -I

X \ Wm DDH-II 1

LEGEND

Slate

= Shale

E Limy shale

X Limestone

P Shaly limestone

E Dolomite

Gossan

-I Channel sample ;-l 1961 sample, -2 1962 sample

x Specimen sample

DDH-9t Diamond-drill hole

Fault zone

0 20 40 60

Scale, feet

FIGURE 12. - Plan of Brown Bear Zone.
\\eF<:ui projected to plane D-D

Altered tered V°\~cor" X l dtc

I LEGEND /

\° ~2.6 Pounds of mercury /LGN NOTE-: All driliholes II per ton dl 2.6 Pounds of mercury projected to plane C-C'\O p per ton

0 ° 20 40 0/° 20 40

AScaIe , feeet Sca le, fteet

FIGURE 13. - Section on Line CC, Brown Bear Zone. FIGURE 14. - Section on Line DD, Brown Bear Zone. VOICQ~~~~~~~~~~~~~~~~~~n Ic volcanic~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~1
TABLE 12. - Petrographic analyses of Brown Bear Zone samples

_ _____ Sample

5-8 518-0 15-2 17-2 19-2 21-2 25-2 29-2 31-2 34-2 37-2 38-2 39-2 42-2 43-2 44-2 47-2 51-2 54-2 57-2

Rock classification:

Clay ............. - - - C C - - - - - C - - - - C - C - C

Dolomite .......... C C C _ C C - - C _ C C C C _ C _ _ _ 

Gossan ............ - - - - C _ _ _ _ _ _ _ _ _ _ _ 

Limestone..........- - - C - - - - - - - - - - C -

Mineral:

Calcite ........... - M T - - M F P M - _ T M M F S F _ P -

Chlorite ...... - - - P P F - - - - P - _ P - P - A

Cinnabar ...... P - - - - M M T T F T P S F F - - T - -

Dolomite ...... A P P - M P P M _ P - A P P P T P M - T

Illite ......- - - A A -- - - - A _ A - A - S

Kaolin minerals... - - - F A _ - - - - S - _ - M - - M A

Limonite .......... - - F S - F T A _ - F T F T S T S M A

Oligoclase ........ _ - - T -_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

Quartz ... T 1M4 T A A - _ M A _ M A S A

P--Predominant .................... Over 50 percent.

A--Abundant ...................... 10 - 50 percent.

S--Subordinate .................... 2 - 10 percent.

M--Minor ...................... 0.5 - 2 percent.

F--Few ...................... 0.1 - 0.5 percent.

T--Trace .................... Less than 0.1 percent.

C--Rock classification.

Note: Samples 5-8 and 518-0 are specimen samples; no chemical assay.
30

TABLE 13. - Chemical analyses of Brown Bear Zone grid samples1

Sample Line Interval, Width, Percent Sample Line Interval, Width, Percent

_ __ _ feet feet mercury feet feet mercury

15 1 0- 9 9 <0.01 36 5 12-19 7 1.96

16 1 9-12 3 <.01 37 5 19-22 3 .03

17 1 12-13 1 <.01 39 6 0- 4 4 .01

18 1 13-15 2 <.01 40 6 4- 5 1 .21

19 1 15-16 1 <.01 41 6 5-13 8 .05

20 1 16-18 2 <.01 42 6 13-15 2 2.03

21 2 0- 7 7 1.00 43 6 15-19 4 .71

22 2 7-14 7 .24 44 6 19-20 1 <.01

23 2 14-15 1 <.01 45 7 0- 4 4 .02

24 2 15-20 5 <.01 46 7 4- 6 2 <.01

25 3 0-10 10 1.46 47 7 6-10 4 <-.01

26 3 10-14 4 1.09 48 7 10-18 8 .02

27 3 14-23 9 <.01 49 7 18-20.5 2.5 <.01

28 4 0- 2 2 .35 50 7 20.5-21 .5 1.30

29 4 2- 3 1 1.84 51 7 21-22 1 1.26

30 4 3- 9 6 .20 52 8 0- 9 9 <.01

31 4 9-10 1 .40 53 8 9-14 5 <.01

32 4 10-15 5 1.45 54 8 14-16 2 <.01

33 4 15-23 8 .02 55 8 16-20 4 .01

34 5 0- 7 7 3.09 56 8 20-23 3 .03

35 5 7-12 5 3.37 57 8 23-24 1 .81

1 Sample locations are shown in figure 12.

Note: Samples taken in 1962; no petrographic or spectroscopic analyses made.

WORK BY THE BUREAU OF MINES

Transportation

The isolation and complete lack of roads, trails, and navigable rivers

presented difficulties in getting equipment to this deposit. Permafrost, ice

lenses, rivers, and swamps canceled any thought of going overland except on

foot during the summer months. The first examination in 1958 was accomplished

by landing a light plane with large tires on the conglomerate formation east

of the deposit and walking the remaining few miles. The landing room was

strictly marginal and required maximum performance from both plane and pilot.

In 1959 a three-man Bureau field party spent the summer at the deposit.

A helicopter was used to bring in camp equipment and men. An airstrip about

500 feet long and 30 feet wide was scratched and smoothed out by hand shovel

on what is now the south end of the present airstrip. A small plane used this

field throughout the summer, but landing conditions were somewhat hazardous.

The moss, which grows during the summer, presented one of the major problems.

It was best removed and kept down by burning; this had to be done by burning

small patches at a time so as not to start a major tundra fire.

In the fall of 1960 two crawler-type tractors, a 16-ton and an 8-ton,

both equipped with wide pads and winches, a diamond drill with accessory
31

equipment and 500 feet of AX drill rods, pumps, tools, and 500 gallons of gas

were flown to Farewell by U.S. Air Force planes. The total weight of this

equipment was 72,000 pounds. Two thousand gallons of diesel fuel were flown

to Farewell by a commercial tanker. An 8- by 16-foot wanigan was built at

Farewell. Three freighting bobsleds plus oil barrels were obtained from the

Federal Aviation Agency as surplus equipment, as was the material to build the

wanigan. The sleds were repaired and the wanigan was mounted on one sled and

the other two sleds were decked with 2- and 3-inch planks and loaded with all

of the rest of the equipment.

On March 1, 1961, this outfit, pulled by the two tractors, left Farewell;

it arrived at White Mountain March 11 over the route shown in figure 2. The

distance traveled was about 60 miles. The trip was made by four Bureau

employees in subzero temperatures as low as -40° F. The larger tractor broke

through the ice on a small lake within 3 miles of the deposit into 16 feet of

water; the temperature was -35° F. The driver was rescued in less than 5

minutes; the tractor was retrieved in May, and all equipment was at White

Mountain by June 1.

A 2,500-foot airstrip was cleared at the deposit and all fuel oil and

supplies after this was accomplished were flown in. Fuel oil was flown to

Farewell by commercial tanker in bulk 2,000-gallon lots and there put in

55-gallon drums; it was then flown 5 barrels at a time by twin-engine plane

to White Mountain. All other supplies were flown directly from McGrath or

Anchorage.

The trip out with heavy equipment was made to McGrath in the spring of

1964 in 12 days by three Bureau employees without difficulty. The distance

of about 100 miles was traveled in subzero temperatures as low as -40° F or

colder. The trip out was made with a much lighter load than the trip in as

practically all of the lighter equipment was flown out in the fall of 1963 by

plane. Experience proved that it is much less expensive and more efficient to

provide an airstrip when possible and fly equipment in rather than to winter

freight it over any great distance, especially over a route that has not been

traveled before.

Augering

In 1960, about 500 1-1/2-inch-diameter short length auger holes were

drilled in the area with a power auger. The easily portable auger, powered

with a standard chain saw 9-hp motor, weighed only 40 pounds. The auger

attachment could be removed in a few minutes and a chain saw blade put on,

converting it back to a standard chain saw. The continuous flight augers were

each 3 feet long and had a flatter pitch than standard coal boring augers; the

distance between flights was equal to the diameter of the auger (1-1/2 inches).

This gave a better return of augered material. Detachable tungsten carbide

bits of the type used in roof bolting were used. The type of bit found most

satisfactory was a very flat faced bit; those with long prongs were useless in

this fractured limestone, dolomite, and shale. Snap button couplings were

first used, but proved unsatisfactory; a high-strength alloy pin and cotter

key was found to be the most satisfactory coupling. Two men were required to
32

operate the auger. The type of auger used did not have a reverse, but a

reverse is desirable.

This highly satisfactory augering equipment was used to drill over 7,000

feet of hole. Bit wear was negligible. The maximum depth that could be

augered was 20 feet, but most holes were bottomed at around 10 feet. The

equipment would not drill frozen gravel. The Central Zone was discovered by

augering, which was used extensively in reconnaissance work in locating

trenches as even trace amounts of cinnabar could be detected in the field by

visual methods and panning. All auger hole cuttings were assayed and many

were panned, but the presence of cinnabar could invariably be detected by a

bright red streak on the bit. Holes had both a hole number and a line number

and all hole locations were marked by a lath. Those that had cinnabar were

additionally marked with colored flagging. A Brunton survey was made of all

holes and a field map kept.

Explosives

Fifteen- and 45-pound lined-cavity beehive-shaped demolition charges were

obtained from the U.S. Army and flown to McGrath via the Alaska Air National

Guard. They were brought to White Mountain from McGrath by helicopter.

Holes having depths of 5 to 6 feet and diameters of 6 to 8 inches were

obtained with these shaped charges in fractured and frozen dolomite. The

45-pound charge gave very little more penetration (usually less than a foot

more) than the 15-pound charge. Penetration in coarse frozen gravel was about

3 to 4 feet; in this material boulders as large as 2 feet in diameter were

numerous and were invariably found at the bottom of the hole, effectively

blocking further penetration. A shallow surface crater about 3 feet in diameter and 18 inches deep was formed by the explosive charge; below this there

was a 6- to 8-inch borehole filled with loose, warm, finely pulverized material that could easily be removed by hand or scoop. Firing another charge on

top of the hole created by the first charge gave little, if any, additional

penetration. Experience elsewhere in Alaska in fine frozen gravel and soil

gave about 10-foot penetration where the use of several shaped charges and

about 15 pounds of TNT in the bottom of each hole usually resulted in a pit

about 12 to 14 feet deep and 8 to 10 feet in diameter. Frozen material is

often thrown for several hundred feet. At White Mountain, these charges,

especially the 45-pound charge, usually set the dry tundra on fire.

Trenching

Almost 12,000 linear feet of bulldozer trenching was done. Trenches

were 10 feet wide and all were in permafrost. About 16 feet was the maximum

depth and most trenches were 8 to 10 feet deep. Even minor cinnabar mineralization is easily seen because of the streak left by blade and track. The

walls of many trenches were panned to aid in tracing the source of cinnabar

float. Considerable drainage trouble was encountered in several trenches and

care had to be taken to avoid getting stuck in frost boils. One tractor was

always kept in a safe area so it could be used to winch out the mired one and

it is doubtful if much work would have been accomplished with one tractor
33

alone. Both had winches which were very necessary in hauling out mired tractors and in freighting. It is also questionable if the 16-ton tractor would

have been retrieved from the lake if the 8-ton tractor had not had a winch.

Core Drilling

All diamond drilling was done with AX rods and bits, except holes Nos. 6,

7, and 13 which were drilled with BX bits, and all collaring was BX size.

Permafrost was always present. Considerable difficulty was experienced in

cementing owing to the excessive cold in the hole. A mixture of lumnite and

portland cement which would set up in 15 minutes on the surface would take 3

to 4 hours or more in the hole. Even a mixture used for a flash set of less

than 5 minutes would do no better. The ratio found best suited for these conditions was 75 percent lumnite and 25 percent portland. This would set up

in about 6 to 8 hours and gave the best strength and all around results.

Water had to be pumped for as far as 3,500 feet with about a 200-foot

lift. Aluminum and plastic pipe was used for waterlines. Parka squirrels

caused some trouble by eating the plastic hose until it was put in that section of line nearest the camp and the squirrels fed table scraps at the camp.

They seemed to prefer the table scraps to the plastic pipe. Water was

obtained by damming small streams with sand bags and lining the dam and pool

back of the dam with polyethylene, since water had to be conserved. The

squirrels also ate the polyethylene; porcupines ate the plywood core boxes.

Fourteen diamond-drill holes were drilled in 1961-62 for a total of 1,428

linear feet. The longest hole was 232.5 feet, this being the maximum that was

practical to drill in permafrost working a single 8-hour shift.

Stream Sampling

Samples of stream gravels, minor drainage courses, and places where a

residual placer concentration of cinnabar would likely occur were taken in a

wide area around the deposit (figs. 3, 15), and panned down to a concentrate.

A spectroscopic analysis (table 5) was made of all concentrate and a chemical

analysis (table 6) was made of those in which cinnabar could be seen visually

and in a few of those where cinnabar was detected by the spectroscope. An

attempt was made to obtain pan concentrate of all the streams that cut the

Farewell Fault for about 15 miles on the north side of Big River. All these

streams are filled with coarse gravel, boulders, and glacial till. Bedrock

could not be reached and the results were inconclusive though two samples, 78

and 79 (fig. 2), indicated that mercury might be present in this area.

Geophysical

A resistivity and self-potential survey made over the Brown Bear, Central,

and South Zones gave negative results in indicating cinnabar mineralization

known to be present. Results differentiated between siliceous dolomite and

the shale, but this was more readily determined with a prospector's pick and

visual observation. It is possible closer work with resistivity might have

picked up fault formations or clay material possibly representing courses of

mineralizing solutions. No such results were obtained.
34

LEGENDes1A

SampleGUR io 15. LoainoAtraeocnraeSmls
35

BIBLIOGRAPHY

1. Brooks, Alfred H. The Mount McKinley Region, Alaska. U.S. Geol. Survey

Prof. Paper 70, 1911, pp. 124-129.

2. Fernald, Arthur T. Geomorphology of the Upper Kuskokwim Region, Alaska.

U.S. Geol. Survey Bull. 1071-G, 1960, pp. 191-279.

3. Pewe, Troy L. and Others. Multiple Glaciation in Alaska. U.S. Geol.

Survey Circ. 289, 1953, pp. 6-7.

4. Sainsbury, C. L., and E. M. MacKevett, Jr. Structural Control in Five

Quicksilver Deposits in Southwestern Alaska. Paper in Short Papers in

the Geological Sciences. U.S. Geol. Survey Prof. Paper 400-B, 1960,

pp. B35, B38.

5. Spurr, J. E. A Reconnaissance in Southwestern Alaska in 1898. U.S. Geol.

Survey 20th Annual Report, pt. 7, 1900, pp. 121-126.
36

APPENDIX A. - LOGS OF TRENCHES

Under the heading "Sample" in the following logs of trenches, the columns

"C" stand for chemical analysis and "P" for petrographic analysis. Petrographic analyses are found in appendix B. Chemical analyses are with the

logs. Sample numbers listed under these columns are in chronological order

by year; that is, 6-1 means sample 6 taken in 1961, 227-2 means sample 227

taken in 1962, and 92-3 means sample 92 taken in 1963. The chronological

order of these samples does not necessarily coincide with the chronological

numbering of the trenches; sample numbers are not in an unbroken series; that

is, in sample numbers from 1 to 150 for 1962, numbers will be missing and not

listed. Analyses of samples listed under columns in logs will be found in

appropriate tables. Unless stated otherwise, samples were selected as typical

specimens of the material described in the log interval. Where mercury mineralization appeared to be of sufficient size and importance, the showing was

channel sampled, diamond drilled, or both.

Trench 1

(figure 7)

O = West end Length: 133.0 feet

Interval, Sam le Description Percent

feet C P mercury

0- 42 - - Black, thin-bedded shale . 42- 50 3-1 3-1 Black, fine-grained, blocky, limy shale .......... 0.02

50- 84 4-1 4-1 Tan to brown shaly dolomite, blocky fracture .02

pattern, limonite stain on fracture surfaces.

84- 96 5-1 5-1 Light gray dolomite, blue-gray fault gouge at .01

86 feet.

96-104 6-1 6-1 Dark gray dolomite, minor calcite veinlets, 2.09

limonite stain on fractures, cinnabar disseminated in small blebs and lenses, about

1 foot of additional trenching into bedrock

removed most of mercury mineralization.

104-133 7-1 7-1 Black, broken limestone with many calcite .02

_________ stringers, end trench.
37

Trench 2

(figure 7)

0 = West end Length: 100 feet

Interval, Sam le Description Percent

feet C P mercury

0- 18 - - Dark gray shale .

18- 23 8-1 8-1 Shaly limestone, abundant quartz and limestone <0.005

23- 25 9-1 9-1 Fault gouge composed of carbonaceous shale and .005

limestone.

25- 40 10-1 10-1 Dark gray, hard limestone, calcite stringers.. <.005

40- 50 11-1 11-1 Gray to yellow, brecciated dolomite ........... <.005

50- 61 12-1 12-1 Yellow, gray to yellow, brecciated dolomite; 1.53

13-1 13-1 erratic and widely disseminated cinnabar, 2.42

minor calcite (see figure 12 and table 13 for

channel samples).

61- 81 14-1 14-1 Gray, brecciated dolomite, a greater amount of 3.40

15-1 15-1 disseminated cinnabar than 50-61 feet. Fault 2.53

16-1 16-1 gouge at 81 feet (17-1) (see figure 12 and 11.30

17-1 17-1 table 13 for channel samples). .005

81-100 - 18-1 Dark gray to black limestone, much calcite ....

Trench 3

(figure 7)

0 = West end Length: 72 feet

Interval, Sam le Description Percent

feet C P mercury

0- 16 - 19-1 Hard, brown gossan, looks like limestone with _

limonite at shale contact. Petrographic

shows a trace of cinnabar.

16- 19 - 20-1 Black dolomite ................................ _

19- 22 21-1 21-1 Broken dolomite, rusty iron stain on fractures 0.01

22- 23 22-1 22-1 Fault gouge, shale .. 01

23- 44 23-1 23-1 Gray to yellow, brecciated dolomite, no .04

24-1 24-1 visible cinnabar, 6-inch fault gouge at <.005

44 feet (24-1).

44- 72 - - Black limestone, numerous calcite veins .
38

Trench 4

(figure 7)

0 = West end Length: 88 feet

Interval, Sam le Description Percent

feet C P _ mercury

0- 7 25-1 25-1 Dark gray shale .......... ..................... <0.005

7- 18 26-1 26-1 Gray, limy shale, iron stain on fractures ..... .005

18- 29 27-1 27-1 Gray to yellow broken shale ................... .005

29- 33 - 28-1 Rusty dolomite ................................ _

33- 34 - 29-1 Fault gouge, shale ............................

34- 39 - 30-1 Gray shale .................................... _

39- 50 31-1 31-1 Gray dolomite, dolomitic shale, fault gouge .005

32-1 32-1 (32-1). .01

50- 88 33-1 33-1 Black limestone ............................... . .01

Trench 5

(figure 5)

0 = West end Length: 200 feet

Interval, Sam le Description Percent

feet C P mercury

0- 16 - - Dark gray shale .

16- 31 34-1 34-1 Yellow dolomite, trace cinnabar . ........ 0.02

31-200 35-1 35-1 Light gray, partially brecciated dolomite, .02

minor shale.

Trench 6

(figure 5)

0 = West end Length: 700 feet

Interval, Saple Description Percent

feet C P mercury

0-163 35A-l 35A-1 Dark gray, thin-bedded, limy shale .......... 0.03

163-347 36-1 36-1 Black, fine-grained, blocky, dolomitic .03

shale, iron stain on fractures.

347-365 - - Blue-gray fault gouge, N 10 W ............... _

365-480 37-1 37-1 Light gray dolomite ......................... .03

480-534 200-2 200-2 Small lenses of cinnabar 1 to 6 inches wide 3.63

and as much as 2 feet long, all striking

east and west in area about 4 feet square

at 534 feet.

534-565 39-1 39-1 Dark gray to black limestone, trace cinnabar .03

at 560 feet. Formation similar to that of

east end of trenches 1 to 4.

565-620 - 201-2 Gray limestone, fine-grained, thin-bedded -

calcite.

620-629 - Fault gouge, strike N 100 E .................

629-700 _ - Dark gray limestone .........................
39

Trench 7

(figure 5)

0 = West end Length: 245 feet

Interval, Sample Description Percent

feet C P mercury

0-100 40-1 40-1 Dark gray to black, limy shale, platy, 0.005

thin-bedded. Beds strike N 250 W and

dip 85° W.

100-105 41-1 41-1 Altered volcanic or trachyte, strike .01

205-2 N 25° W.

105-140 42-1 42-1 Black, dense dolomite, calcite stringers, <.005

43-1 43-1 angular inclusions of calcite, minor

206-2 dolomite (43-1).

140-144 44-1 44-1 Dark yellow dolomite, limonite stain on .01

fractures.

144-222 45-1 45-1 Light gray dolomite, considerable calcite <.005

and quartz, minor limonite, trace of

cinnabar at 214 feet.

222-226 46-1 46-1 Fault gouge, strike N 250 W . .<.005

226-237 - 213-2 Dark gray dolomite, spherulite on nodular -

surface. Similar to South Zone section.

237-239 - - Fault gouge .

239-245 47-1 47-1 Dark gray, dense limestone, calcite <.005

stringers, minor quartz.

Trench 8

(figure 5)

0 = West end Length: 234 feet

Interval, Sam le Description Percent

feet C P mercury

0- 53 - - Dark gray, limy shale, broken ................... .

53- 56 - - Fault gouge, shale, strike N 250 W .

56-134 - - Gray, broken limestone and limy shale .

134-143 - - Dark gray dolomite, trace cinnabar .

143-195 - - Gray, broken limestone and limy shale .

195-200 - - Black fault gouge with shale fragments, _

strike N 25° W.

200-227 - - Limy shale .

227-234 - - Blue fault gouge. ._.. . .
40

Trench 9

(figure 5)

0 = West end Length: 175 feet

Interval, Sample Description Percent

feet C P mercury

0- 81 _ _ Dark gray, broken, limy shale, limonite stain _

on fracture surfaces.

81-158 _ _ Gray, broken dolomite, trace cinnabar at 152 _

feet.

158-164 _ _ Fault gouge, shale .

164-175 _ _ Calcareous, thin-bedded sandstone, shale ._.....

Trench 10

(figures 5 and 8)

0 = West end Length: 160 feet

Interval, Sample Description Percent

feet C P mercury

0- 10 _ - Gray to black, thin-bedded siltstone.........

10- 60 - Gray to black, limy shale, strike bedding _

N 250 W, vertical dip.

60- 91 - - Gray, broken dolomite, 3-inch altered zone -

at contact with shale (60 feet).

91- 93 50-1 50-1 Gray dolomite, 1-foot-wide zone of erratic 2.22

217-2 cinnabar mineralization which starts in 2.73

north wall and continues to south wall

(N 50° W). Cinnabar occurs as fracture

coating and is best in north wall of

trench (see fig. 8).

93-129 - - Gray dolomite _

129-130 - - Gray dolomite, minor cinnabar .

130-141 - - Yellow dolomite, less hard than gray _

dolomite.

141-143 - - Fault gouge .

143-160 51-1 51-1 Reddish shale, limonite coating on fractures. .005

Petrographic analysis shows trace of

cinnabar which was not noticed in field.
41

Trench 11

(figure 5)

0 = West end Length: 270 feet

Interval, Sample Description Percent

feet C P mercury

0- 11 - 170-2 Light gray dolomite with dark gray dolomite -

inclusions.

11- 15 - - Blue fault gouge, strike N 50 E .

15- 36 - - Light gray dolomite .

36- 54 - 172-2 Shale fault gouge (172-2), strike N 250 W, -

at 40 feet is 0.5 foot of altered limestone

which also strikes N 250 W.

54- 63 - - Gray to yellow friable dolomite . 63- 74 - - Light gray, hard dolomite .

74- 78 173-2 173-2 Light gray, hard dolomite, small dissemi- 0.03

48-1 48-1 nated blebs and lenses of cinnabar, from

78 to 80 feet, a 1/8- to 1/4-inch-wide

veinlet of cinnabar in center of trench.

78- 92 - - Light gray, hard dolomite .

92- 95 174-2 - Light gray, hard dolomite, with disseminated .13

blebs and small lenses of cinnabar.

95- 99 - - Light gray dolomite, no cinnabar .

99-100 175-2 175-2 Light gray dolomite, disseminated cinnabar .11

100-110 - - Light gray dolomite .

110-111 176-2 - Light gray dolomite, 6-inch zone of cinnabar 2.92

48-1 48-1 that strikes N 250 W. All of the mineral- 1.37

49-1 49-1 ized sections of the trench from 74 to 111 6.54

feet strike about N 250 W. Sample 48-1 is

a composite sample of numerous lenses and

blebs of cinnabar with considerable dolomite. 49-1 is of selected high-grade

cinnabar specimens.

111-121 - - Light to medium gray dolomite . 121-122 177-2 - Light to medium gray dolomite with dissemi- .47

nated blebs and lenses of cinnabar.

Note: Special channel samples 56-3 to 67-3

have been taken over this area (74 to 122

feet) and are found in table 13.

122-138 - - Light to medium gray dolomite .

138-164 - 178-2 Fault gouge, shale, strike of contact at -

164 feet is N 200 W.

164-210 - - Light gray dolomite . 210-246 - - Dark gray, brecciated dolomite .

246-270 _ _ Light gray dolomite ._.. . .. .
42

Trench 12

(figure 5)

0 = West end Length: 165 feet

Interval, Sam le Description Percent

feet C P mercury

0- 20 - 182-2 Gray to black, shaly limestone, calcite .

20- 50 - 183-2 Yellow dolomite, minor limonite .

50- 89 - - Light gray to yellow, fine-grained dolomite -

89-135 - - Light gray and gray dolomite, minor limonite -

135-159 - 186-2 Fault gouge, similar to 138-164 feet, trench -

11, dolomite.

159-165 _ 187-2 Light yellow dolomite _.......

Trench 13

(figure 5)

0 = West end Length: 184 feet

Interval, Sa ple Description Percent

feet C P mercury

0- 49 - Black, fine-grained, shaly limestone,

calcite stringers; bedding strike

N 25° W, dip 850 W.

49- 88 - 189-2 Black, fine-grained shale ................... _

88- 96 190-2 190-2 Altered volcanic or trachyte ................ <0.01

96-169 - - Black, rusty yellow, silicified limestone, -

calcite stringers.

169-170 - - Fault gouge, strike normal to trench ........ _

170-173 - 192-2 Light rusty tan dolomite .................... _

173-174 - - Fault gouge, strike normal to trench ........ _

174-184 - 193-2 Dark gray dolomite, much calcite ............ _

Trench 14

(figure 5)

0 = West end Length: 190 feet

Interval, Sam le Description Percent

feet C p _ mercury

0-100 - - Dark gray, fine-grained, thin-bedded limestone, _

strike of bedding N 22° W, dip 850 to 900 W.

100-190 - - Light to medium gray, very siliceous dolomite, _

no bedding, minor limonite stain. At 97 feet

blue clay fault gouge 8 inches wide starts

and enters west wall at 114 feet. Strike at

100 feet is N 210 W. There is more iron stain

_________ present at 100 feet than elsewhere.
43

Trench 15

(figure 5)

Not finished because of steep hillside and depth of overburden; probably

dolomite; negative results in panning of overburden for cinnabar.

Trench 16

(figure 5)

0 = West end Length: 331 feet

Interval, Sam le Description Percent

feet C P mercury

0- 41 - - Light gray, siliceous dolomite, a few very -

small vugs or cavities.

41- 81 - - The same as 0 to 41 feet except much more -

limonite stain.

81- 99 - 150-2 Dark gray, fine-grained dolomite .............. .

99-110 - - Light gray, siliceous dolomite, a few very -

small vugs or cavities.

110-120 - 151-2 Dark gray to black, fine-grained, siliceous -

dolomite.

120-130 - - Gray, slightly brecciated dolomite . 130-227 - 153-2 Light gray and yellow, siliceous dolomite, -

limonite stain. Very siliceous dark fragments of dolomite in lighter groundmass.

At 133 feet is minor disseminated cinnabar

in siliceous hot springs deposit.

227-245 - - Light gray, siliceous dolomite . 245-248 - 156-2 Dark gray dolomite ............................

248-251 - - Fault gouge, N 250 W . 251-331 - - Black, fine-grained limestone, calcite

stringers 330 to 331 feet, strike of bedding

N 50° E, this section similar to east end

of Brown Bear trenches.
44

Trench 17

(figure 5)

0 = South end Length: 228 feet

Interval, Samle Description Percent

feet C p mercury

0- 5 - - Black, fine-grained, siliceous limestone, has a -

platy structure, small calcite stringers.

5- 12 - - Blue clay fault, strike S 450 W . 12- 35 - 121-2 Greenish black dolomite, petrographic analysis -

shows a trace of cinnabar, few small calcite and

quartz stringers.

35- 64 - - No bedrock .

64- 68 - - Black, fine-grained dolomite, small quartz _

stringers.

68-121 - - Black to yellow, broken dolomite .

121-139 - - Yellow to gray, siliceous dolomite .

139-155 - 125-2 Dark gray to yellow, brecciated, siliceous dolo- -

mite, reddish cast.

155-195 135-2 135-2 Dark gray to yellow dolomite, broken and brec- 18.7

136-2 136-2 ciated. 135-2 loose cinnabar-bearing sand in west 40.0

140-2 140-2 wall of trench. 136-2 pieces of geyserite con- .03

140A-2 140A-2 taining cinnabar in the above sand. These samples 6.56

at 170 feet. 140-2, 140A-2 loose unconsolidated

material in west wall of trench at 175 feet.

195-228 _ _ Dark gray to yellow, brecciated, broken dolomite, -

minor cinnabar at 200 feet.

Trench 17A--Cross Section

(figure 5)

0 = West end Length: 30 feet

Interval, Sam le Description Percent

feet C P mercury

0 - 3.5 - 127-2 This cross trench between trench 17 and trench 18

starts at 184 feet from 0 or south end of trench 17.

Yellow-brown, friable geyserite or siliceous sinter,

has a pumice-like texture.

3.5- 7.5 128-2 128-2 Brown, vuggy, broken limestone .0.13

7.5- 9 129-2 - Brown, vuggy, broken limestone, quartz lenses, 10.36

cinnabar.

9 -11 130-2 - Brown, vuggy, broken, siliceous limestone, more .05

quartz, minor cinnabar.

11 -13 131-2 - Brown, vuggy, broken, siliceous limestone, minor 2.02

cinnabar.

13 -15.5 132-2 - Fine sand (geyserite), light gray to yellow dolomite, 2.98

minor cinnabar as soft paint or coating on fractures

of dolomite.

15.5-18 133-2 - Light gray to light yellow, siliceous, broken dolo- .12

mite; trace cinnabar as soft paint or coating on

fractures.

18 -20 134-2 - . do .......................... .33

20 -30 137-2 137-2 Yellow to gray dolomite, broken and brecciated, minor .20

138-2 138-2 cinnabar. 137-2 is loose material found in large .06

12-inch diameter vug in dolomite rock. 138-2 is

_ part of vug.__Loosematerial in vug is geyserite.
45

Trench 18

(figure 5)

0 = South end Length: 250 feet

Interval, Sample Description Percent

feet C P mercury

0- 33 - 1-2 Black, fine-grained, siliceous limestone with

calcite stringers, has a platy or shaly

structure, occasionally mammillary quartz

on weathered fracture surfaces.

33- 55 - 1-2 Dark gray dolomite, blocky, numerous small _

lenses of calcite, limonite coating on

fracture surfaces.

55- 83 - - Same as 33-55 feet but with less limonite _

83- 89 - - Dark gray to black dolomite with a yellowish _

cast, more siliceous and more limonite than

0-83 feet, small angular inclusions of

shale.

89- 92 - - Dark gray dolomite with minor red and green -

iron stain on fractures, strike of bedding

N 50 E.

92-108 5-2 5-2 Dark gray, very siliceous, fine-grained 0.01

dolomite, irregular blocky fractures.

108-112 7-2 - Same as 89-92 feet, N 50 W .. 01

112-123 - - Greenish gray dolomite, siliceous, cherty, -

many tiny vugs.

123-133 10-2 - Dark gray to black dolomite with a yellowish 11.5

cast, limonite on fractures, small angular

shale inclusions. From 124-131 feet finegrained cinnabar visible in trench walls

(10-2).

133-137 11-2 11-2 Soft reddish yellow dolomite, petrographic .02

analysis indicates a trace of cinnabar.

137-163 - - Dark gray, siliceous dolomite, tiny stringers -

and blebs of calcite.

163-165 13-2 13-2 Soft reddish yellow dolomite .. 01

165-250 - - Gray to dark gray dolomite, some high-grade -

cinnabar float in overburden from 200-250

feet.
46

Trench 19

(figure 5)

0 = West end Length: 193 feet

Interval, Sample Description Percent

feet C P mercury

0- 18 - - Black to gray, shaly limestone .

18-100 - - Black, fine-grained shale .

100-128 - - Black to rusty, fine-grained, siliceous _

limestone, calcite stringers.

128-137 - - Fault, poorly exposed .

137-159 - - Black, fine-grained limestone .

159-171 - - Black, fine-grained dolomite, calcite _

stringers.

171-193 - 209-2 Altered volcanic or trachyte .. _....

Trench 20

(figure 5)

0 = West end Length: 418 feet

Interval, Sam le Description Percent

feet C P mercury

0-218 - 195-2 Black, limy shale, few calcite stringers -

218-263 - 209T-2 Black, fine-grained, limy shale, alternating -

in thin-bedded and blocky beds.

263-314 - - Same as 218-263 feet, but with limonite stain -

on fracture surfaces.

314-323 - 211-2 Altered volcanic or trachyte .

323-358 - - Fault gouge, muck, poor bedrock exposures -

358-418 - - Light gray, siliceous dolomite .___....

Trench 21

(figure 5)

0 = West end Length: 359 feet

Interval, Sam le Description Percent

feet C P mercury

0-142 - _ Gray to black, limy shale .

142-200 - _ Gray to black, fine-grained, limy shale .

200-224 - _ Gray to black, fine-grained, limy shale with -

considerable limonite stain on fractures.

224-237 - _ Dark gray limestone ......................... _

237-246 - 196-2 Altered volcanic or trachyte .................. _

246-275 - - Limestone and limy shale ...................... _

275-359 - - Gray dolomite, minor cinnabar at 335 feet ..... _
47

Trench 22

(figure 5)

0 = West end Length: 100 feet

Interval, Sample Description Percent

feet C P mercury

0- 79 - 146-2 Gray to yellow dolomite, limonite coating on _

fractures.

79- 80 - 147-2 Shaly limestone, minor cinnabar .

80-100 - - Light gray, siliceous dolomite ._.....

Trench 23

(figure 5)

0 = North end Length: 125 feet

Interval, Sa ple Description Percent

feet C P mercury

0- 17 _ 218-2 Light to medium gray, siliceous, broken

dolomite.

17- 26 _ - Same as 0-17 feet, but more limonite .

26- 29 220-2 220-2 Dark gray, siliceous dolomite, much limonite. 0.67

221-2 - Blebs and small lenses of cinnabar errati- 2.00

cally disseminated in a poorly defined mineralized zone about 1 foot wide striking

about N 100 W. Mineralization is best at

center of trench and tends to fade or

diminish toward the walls of the trench.

220-2 is sample of average mineralization

in zone, 221-2 is sample of best mineralization in zone.

29- 45 - - Gray to yellow, siliceous dolomite .

45- 47 223-2 223-2 Gray to yellow, siliceous dolomite with .01

224-2 224-2 minor cinnabar. 223-2 is average sample, 1.06

224-2 is sample of best mineralization.

47- 55 - - Gray to yellow, siliceous dolomite .

55- 60 225-2 225-2 Yellow-brown dolomite, erratic cinnabar min- 10.98

226-2 226-2 eralization,dolomite often vuggy. Mineral- 3.13

227-2 - ization strikes N 450 W and could be con- .64

tinuation of cinnabar outcrop exposed in

bank 75 feet to east and 25 feet lower.

225-2 is the top 12 inches of sinter in a

1- by 2-foot lens of cinnabar mineralization, 226-2 is of the mineralized dolomite

under the sinter, 227-2 is average mineralization of zone. Trenching an additional

foot in depth removed all visible cinnabar

except that in trench walls.

60- 61 228-2 228-2 Greenish gray dolomite, minor limonite .03

61- 90 - - Gray to brown dolomite, much iron stain -

90-125 _ - Dark gray to yellow,hardsiliceous dolomite _

with calcite lenses,red iron mineralization.
48

Trench 24

(figure 5)

0 = North end Length: 550 feet

Interval, Sam ple Description Percent

feet C P mercury

0- 83 - - Medium to light gray, siliceous dolomite -

83-153 - - Medium to light gray, siliceous, slightly -

porous dolomite.

153-383 - - Medium gray, siliceous dolomite, zones with -

minor iron, less porous than 83-153 feet.

383-500 - 145-2 Light gray to yellow, siliceous dolomite, -

minor cinnabar at 463 feet.

500-550 - - Light gray to yellow dolomite, considerable -

iron stain.

Trench 25

(figure 5)

0 = West end Length: 170 feet

Interval, Sample Description Percent

feet C P mercury

0- 28 - 159-2 Light gray dolomite, minor cinnabar at 24 -

feet.

28- 58 161-2 - Light yellow to light gray dolomite, red 0.06

iron stain.

58- 86 - - Yellow dolomite, much iron .................. . 86-110 - - Light gray, siliceous dolomite.

110-128 - 165-2 Geyserite, medium gray, very hard and _

slightly porous, slightly reddish cast,

minor cinnabar at 124 feet.

128-145 - - Gray, brecciated, siliceous dolomite, -

limonite coating on fractures.

145-152 - - Gray to yellow, fine-grained dolomite .- 152-154 - 168-2 Geyserite, dark steel gray, brecciated, -

siliceous.

154-170 - - Dark gray to yellow limestone, limonite -

stain.
49

Trench 26

(figure 5)

0 = North end Length: 600 feet

Interval, Sample Description Percent

feet C P mercury

0-600 _ _ Gray dolomite, bedrock poorly exposed in

much of trench, minor erratic cinnabar

lenses in last 75 feet on both sides of

trench, mineralization similar to South

Zone.

Trench 27

(figure 5)

0 = North end Length: 44 feet

Interval, Sample Description Percent

feet C P mercury

0-44 _ - Dark gray to yellow, siliceous dolomite with _

a reddish cast.

Trench 28

(figure 5)

0 = West end Length: 270 feet

Interval, Sam le Description Percent

feet C P mercury

0-270 Partially exposed bedrock, much muck, water,

gray limestone and gray to dark gray limy

shale. No evidence of cinnabar.

Trench 29

(figure 5)

Not excavated to bedrock owing to frost, deep overburden, and caving

trench walls. Much gravel present in walls; loose material in trench bottom

indicates bedrock may be limy shale. No cinnabar mineralization found in

trench.
50

Trench 30

(figure 5)

0 = North end Length: 540 feet

Interval, Sa Ple Description Percent

feet C P mercury

0-100 - - Gray, limy shale, reddish iron stain common as _

coating on fractures.

100-118 - - Gray dolomite .

118-150 - - Gray dolomite and altered volcanic or trachyte.

Starting at 118 feet and 2.5 feet from west wall

of trench and striking N 100 E and entering east

wall at 153 feet was a 1-foot-wide mineralized

zone consisting of a top layer of 3 to 12 inches

of white claylike trachyte then 0.5 to 1 foot of

brown disintegrated dolomite containing much cinnabar. Mineralization abruptly ended at maximum

depth of 1 foot. Additional trenching removed all

evidence of mineralization. The 10 feet of overburden gave no clue to this mineralization.

- 225A-2 White claylike trachyte at 127 feet .

226A-2 226A-2 Rusty brown dolomite with much cinnabar capped by 1 59.3

foot of white claylike trachyte at 118 feet.

227A-2 227A-2 Same as 226A-2 except at 141 feet, vuggy, bright 61.3

red.

228A-2 228A-2 Brown, disintegrated dolomite below the rich 4.05

cinnabar-bearing dolomite, appears to contain no

cinnabar. Suspect sample was salted.

229A-2 229A-2 Rusty claylike trachyte at 135 feet .. 06

- 230A-2 Brown, decomposed dolomite directly under 229A-2 at -

135 feet.

- 231A-2 Trachyte at 134 feet, looks like greenish limestone -

or a greenish coating on black limestone.

- 232-2 Steel gray, fine-grained, fresh trachyte at 134 -

feet.

150-161 - 234-2 Dark gray to black, siliceous and cherty dolomite, -

limonite. 4 feet in toward the center from the

west side of the trench and parallel with the

strike of the trench from 150-161 feet is a 0.5-

foot-wide zone of trachyte that looks like a blue

clay fault gouge (234-2).

161-178 - - Dark gray, fine-grained dolomite . 178-210 - - Gray to dark gray, siliceous shale and argillaceous -

limestone. Strike of bedding is N 25° W.

210-286 - - Same as 178-210 feet with some yellow to brown -

limonite and segments of trachyte as in sample

234-2.

286-315 - 237-2 Yellow to brown, siliceous dolomite with dark -

grains.

315-440 - 238-2 Black, fine-grained limestone .

440-484 - 239-2 Trachyte, looks like gray quartzite, abundant -

sanidine, siderite, and mesitite present.

484-523 - 240A-2 Trachyte, dark gray to rusty gray, looks like -

sandstone or siliceous limestone, petrographic

analysis shows a trace of cinnabar.

523-540 _ 240B-2 Same as 484-523 feet, but no cinnabar .. _....
51

Trench 31

(figure 5)

Deep, caving overburden made it impractical to complete this trench.

Trench 34 exposes bedrock in the area from a better angle.

Trench 32

(figure 7)

0 = West end Length: 145 feet

Interval, Sam le Description Percent

feet C P mercury

0- 5 _ Gray dolomite ................. ,.,,.,.,.. _

5- 16 _ Dark gray, fine-grained, platy limestone . _

16- 17 _ _ Fault gouge, strike N 5° E .

17- 24 _ - Black to gray limestone, platy, dip 850+ to _

west.

24- 26 - - Yellow, siliceous limestone, strike N 200 W -

26- 32 - - Black to gray, platy limestone .................. ,

32- 34 - - Yellow, siliceous limestone .

34- 38 - - Black, very hard, dense dolomite, some quartz -

38-145 - - Yellow to brown limestone, limonite coating on -

fractures.

Trench 33

(figure 7)

0 = West end Length: 315 feet

Very similar to trench 32, alternate zones of dolomite and limestone with

limestone predominating; no cinnabar.

Trench 34

(figure 5)

0 = West end Length: 65 feet

Interval, Sample Description Percent

feet C P mercury

0-65 _ - Gray to yellow dolomite, limonite coating on _

fractures. No cinnabar.
52

Trench 35

(figure 5)

0 = East end Length: 340 feet

Interval, Sample Description | Percent

feet C P mercury

0-340 _ _ Gray to dark gray limestone and shale, limonite

coating on fractures, minor dolomite. No

cinnabar.

Trench 36

(figure 5)

0 = North end Length: 260 feet

Interval, Sam le Description Percent

feet C p mercury

0-260 _ _ Light gray to yellow, siliceous dolomite, minor ..

cinnabar from 65-70 feet, slight green cast to

dolomite adjacent to cinnabar. _

Trench 37

(figure 5)

0 = East end Length: 445 feet

Interval, Sam le Description Percent

feet C P mercury

0-445 _ _ Interbedded sandy shale and limestone; no

cinnabar mineralization.

Trench 38

(figure 5)

0 = West end Length: 230 feet

Interval, Sa pleDescription Percent

feet C P mercury

0-230 _ _ Dark gray, sandy limestone, no cinnabar

mineralization.

Trench 39

(figure 5)

0 = West end Length: 125 feet

Interval, Sam le Description Percent

feet C P me rcury

0-125 _ _ Gray, sandy shale, limestone, no cinnabar

mineralization.
53

Trench 40

(figure 5)

0 = North end Length: 40 feet

Interval, Sam le Description Percent

feet C P mercury

0-40 _ _ Dark gray limestone and dark gray shale; no _

cinnabar mineralization.

Trench 41

(figure 5)

0 = North end Length: 245 feet

Interval, Sa le Description Percent

feet C P mercury

0-245 _ - Dark gray, sandy shale, no cinnabar

mineralization.

Trench 42

(figure 6)

0 = West end Length: 290 feet

Interval, S Description Percent

feet C P mercury

0-290 _ _ Dark gray, sandy shale, minor limonite .

Trench 43

(figure 7)

0 = East end Length: 555 feet

Interval, Sam ple Description Percent

feet C P mercury

0-555 _ _ Trenched to approximately 15 feet; no bedrock, _

all frozen gravel and large boulders. No

cinnabar mineralization or float in overburden.

Glacial gravels.

Trench 44

(figure 7)

0 = East end Length: 128 feet

Interval, Sam le Description Percent

feet C P mercury

0-128 No bedrock, trenched to approximately 12 feet _

in glacial gravels, permafrost to bottom, no

evidence of cinnabar in overburden.
54

Trench 45

(figure 7)

0 = North end Length: 180 feet

Interval, Sam le Description Percent

feet C P mercury

0-180 _ _ No bedrock, trenched to approximately 12 feet _

in glacial gravels, permafrost to bottom, no

evidence of cinnabar in overburden.

Trench 46

(figure 7)

0 = East end Length: 236 feet

Interval, Sam le Description Percent

feet C P g mercury

0-236 No bedrock, permafrost, much muck, frozen silt, e

gravels, poor drainage, no evidence of

cinnabar. Trenched to about 6 feet.

Trench 47

(figure 7)

0 = West end Length: 712 feet

Interval, Sam le Description Percent

feet C P mercury

0-712 _ _ No bedrock, trench to 15- to 20-foot depth in _

places, all glacial gravels and still permafrost to bottom of maximum depth. Many

boulders up to 2 to 3 feet in diameter.

_______ ___ No evidence of cinnabar.

Trench 48

(figure 7)

0 = West end Length: 110 feet

Interval, Sam le Description Percent

feet C p mercury

0-110 _ _ No bedrock, trenched to 10-foot depth, glacial_

gravels, large boulders, all permafrost, no

__L J evidence of cinnabar.
55

Trench 49

(figure 7)

0 = West end Length: 180 feet

Interval, Sa le Description Percent

feet C P mercury

0-180 No bedrock, trench to 10-foot depth, glacial

gravels, all permafrost, no evidence of

cinnabar.

Trench 50

(figure 6)

0 = East end Length: 87 feet

Interval, Sa mpleDescription Percent

feet C P mercury

0-87 Dark gray, thin-bedded, shaly limestone,

strike of bedding N 20° W. vertical dip.

No cinnabar.

Trench 51

(figure 6)

0 = East end Length: 105 feet

Interval, Sa le Description Percent

feet C P mercury

0-105 _ _ Dark gray, thin-bedded, shaly limestone and _

black limestone with calcite stringers, few

hard reefs of limestone, strike of bedding

________ __ N 15° W. No cinnabar.

Trench 52

(figure 6)

0 = South end Length: 300 feet

Interval, Sam le Description Percent

feet C P mercury

0-300 _ 92-3 Medium gray, hard, siliceous dolomite, minor -

calcite and iron stain. Trace cinnabar at

_________ 150 feet.
56

APPENDIX B.--PETROGRAPHIC ANALYSES OF TRENCH SAMPLES

The same numbering system is used here as in appendix A. The following

legend applies to all petrographic samples in appendix B.

P--Predominant .............. Over 50 percent.

A--Abundant .............. 10 - 50 percent.

S--Subordinate .............. 2 - 10 percent.

M--Minor .............. 0.5 - 2 percent.

F--Few .............. 0 .1 - 0.5 percent.

T--Trace .............. Less than 0.1 percent.

C--Rock classification.

X--Detected in sample.

- ample

3-1 4-115-116-1 7-1 8-1 9-1 10-1 11-1 12-1 13-1 14-1

Trench .................. 1 1 1 1 1 2 2 2 2 2 2 2

Rock classification:

Altered volcanic ...... _ - - - -. _ - _ - -

Clay .................. - - - - - - - - -

Dolomite . ...... _ C C C - _ - C C C C

Gossan ................ - - - -

Limestone ............. - - - - C C C C _ _ _ _ 

Shale ................. C - - - - - C -_ _ _ _ 

Springs deposit ....... _ - - - - - - -

Mineral:

Albite ................ - - - - - - - -

Andesine ............ - - - - - - - -

Augite .............. _ _ - - - - - - - -

Biotite ............... - - - - - - - -

Calcite ............... A - - M P A A P _ - F S

Carbon ................ - - - - - A A -_ _ _ -

Chlorite .............. A M -

Cinnabar .............. X X - M - T - - T T S S

Dolomite .............. S A P P - - - - p P P P

Illite ................ A A - - - A A - M _ _ _ 

Kaolin minerals ....... _ S - - - M -_ _ _ -

K-feldspar ............ - - - - - - -

Limonite . ............. S M

Magnetite ............. - - - - - - -

Mesitite .............. - - - - - - -

Muscovite ............. - - - - - - -

Pyrite ............... . _ - - - - T - _ - _ 

Quartz . ............... - - T - - A T - M _ _ _ 

Sanidine .............. - - - - - - - -

Siderite .............. I _ _ I _ . I _ _ I _ I I 
57

Sample

15-1 16-1 17-1 18-1 19-1 20-1 21-1 22-1 23-1 24-1 25-1

Trench ............ 2 2 2 3 3 3 3 3 3 3 4

Rock classification:

Altered volcanic ..... - - - - - - - - - -

Clay ...........

Dolomite ......... C C - - - C C - C - -

Gossan .......... - - - - C - - - - - -

Limestone......... - - - C - - - - - -

Shale........C...... - - C - C C

Springs deposit .....

Mineral:

Albite .......... - - - - - - - - - -

Andesinee.........

Aug ite ..........

Biotite.......... - - - - - - - - - - -

Calcite........... - - - P N -

Carbon ..... ...... - - - - - - - - - - -

Chlorite .... ...... - - - T N - M A - S A

Cinnabar .... ...... F A T - T - T X T T T

Dolomite ........ . P p - - - P P - P - N

Illite ..... ...... - - P - - - P - P p

Kaolin minerals....... - - - P - - - - - -

K-fe ldspar ........

Limonite .... ...... A - - - S - -- M S

Magnetite ........

Mesitite.......... - - - - - - - - - - -

Muscovite .... ..... - - - - - - - - - - -

Pyrite ..... ...... - - - T - - - - - -

Quartz ..... .......- - - - M -

Sanidine ..................- -

Siderite ..................- ISample____ __ __

26-1 27-1 28-1 29-1 30-1 31-1 32-1 33-1 34-1 35-1 35A-1

Trench............ 4 4 4 4 4 4 4 4 5 5 6

Rock classification:

Altered volcanic...... - - - - - - - - - - -

Clay ...........

Dolomite .... ...... - - C - - C - - C C -

Gos san ..... ...... - - - - - - - - - - -

Limestone .... ..... - - - - - - - C - - -

Shale ..... ...... C C - C C - C - - - C

Springs deposit .....

Mineral:

Albite .......... - - - - - - - - - - -

Ande sine ......... - - - - - - - - - - -

*Augite .......... M - - - - - - - - - -

Biotite ................. -

Calcite.......... A S M - - S-f - P A T M

Carbon.-.................. -

Chlorite....S...A........- - -ACinnabar ......... X - K T - X K - T T T

Dolomite ......... - - P - - P A - P p -

Illite .......... A P - P p - P - -

Kaolin minerals...... - - - - - - - - - - -

K-fe ldspar ........

Limonite.S............... T - -

M~agnetite ........

Mesitite.-................ - -

Muscovite.-...............- -

Pyr ite .................. - -

Quartz .......... - - - M - - S - - - -

Sanidine ......... - - - - - - - - - -

Siderite ................ -
58

-- 39-1 ~~~~~ S a m p l e

36-1 37-1 38-1 3 40-1 1 41-1 42-1 43-1 44-1 45-1 46-1 Trench .................... 6 6 6 6 7 7 7 7 7 7 7 Rock classification:

Altered volcanic ........ - - - C _ _ _ _ _ Clay ..... .. ...... _ - - Dolomite ................ C C C C _C 

Gossan .................. - -

Limestone ............... - - C

Shale ................... C - C C C

Springs deposit ......... - -

Mineral:

Albite .................. - -

Andesine ................ - -

Augite .................. - -

Biotite ..... . , _ _ _ _ Calcite ............... S f P _ M-f _ Carbon .................. - -

Chlorite ................ - - A _ A _ _ A

Cinnabar ................ - -_ T T

Dolomite ................ A P - S p P P P P Illite .................. - - P P A A

Kaolin minerals ......... - - -

K-feldspar .............. - - - A

Limonite ................ - - A

Magnetite ............... - -

Mesitite ................ - -

Muscovite ............... - -

Pyrite .................. - -

Quartz .................. - - S M _ _ _ _ _ _ A Sanidine ................ - -

Siderite ................

- - - ~~~~~Samzle ___

47-1 48-1 49-1 50-1 51-1 1-2 2-2 5-2 10-2 11-2 13-2 121-2 Trench 7................7 11 11 10 10 18 18 18 18 18 18 17 Rock classification: - _ Altered volcanic - - - -_ _ _ _ _ _ _ _ Clay .. ..........

Dolomite ........... - C C C _ - C C C C C C

Gossan ............. - - -

Limestone.C.......- C _ C _ _ _ Shale ... ._ _ _ _ _ C _ _ Springs deposit .... - - - _ _ _

Mineral:

Albite ............. - - -

Andesine ........... - - -

Augite ............. - - -

Biotite ..... ......

Calcite ............ P - F T - P M M M _ _ S Carbon ............. - - - Chlorite ........... - - - F _ _ _ Cinnabar ........... - T A S T _ _ T T _ T Dolomite ........... - p p P - P P p p P P Illite ............. - - - P Kaolin minerals .... - - - _ _ _ _ _

K-feldspar ......... _ - -

Limonite ........... - - - S T F _ M S _ Magnetite .......... _ _

Mesitite ........... _

Muscovite .......... _ _

Pyrite ...... _ _ _ _ _ _

Quartz ...... _ S _M - _ M _ S Sanidine ........... _

Siderite ...........
59

______ ___ ___ _ _ _____Sam ple _ _ _ _ _ _ _

125-2 127-2 128-2 135-2 136-2 137-2 138-2 140-2 142-2

Trench ............. 17 17 17 17 17 17 17 17 14

Rock classification:

Altered volcanic .......- - - - - - - -

Clay...... ...... ...... ....-

Dolomite .C........... C - C C C C

Gossan........ ....... ......-

Limestone......C...........- -

Shale ............

Springs deposit.....C.... - C C C -

Mineral:

-Albite...... ...... ...... ..-

Andesin e .......... ........ -

Augite...... ...... ...... .. -

Biotite...... .............- -

Calcite............T A P - - - - -

Carbon........ ....... ......-

Chlorite....S.............. -

Cinnabar ........... S S A T - A

Dolomite ......... P M - P 5 A P A P

Illite...... ...... ...... ..

Kaolin minerals...S.......... - -

K-feldspar...................-

Limonite...................

Magnetite.................. -

Mesitite...................

Muscovite.................. -

Pyrite...................

Quartz..........M- P 5 M P P M S

Sanidine ...................

Siderite ...................

________ ~~~~Sample_ _ _ _ _ _ _ _

145-2 146-2 147-2 150-2 151-2 153-2 156-2 157-2 159-2

Trench ............. 24 22 22 16 16 16 16 16 25

Rock classification:

Altered volcanic .......- - - - - - - -

Clay...... ...... ...... ....-

Dolomite ........... C C - C C C C - C

Gossan....................- -

Limestone........C...... - - C -

Shale ............

Springs deposit...........- - C - -

Mineral:

Albite...... ...... ...... ..- -

Andesine...................- -

Augite...... ..............- -

Biotite...................- -

Calcite............M - P - T T T P -

Carbon...... ...... ...... ..- -

Chlorite4...........- - S - - - - - -

Cinnabar ..........- T - T M T - T

Dolomite ......... P P M P P A P - P

Illite ............- - S - - -- -

Kaolin minerals........- - M - - - - -

K-feldspar .......... - - - - - - - -

Limonite ...............- - - F

Magnetite...........- - - - - - - -

Mesitite ...........- - - - - - - -

Muscovite...........- - - - - - - - -

Pyrite ............- - - - - - - -

Quartz ............- - T - - P T M -

San idine...................- -

Siderite ...................
60

Sample

165-2 168-2 170-2 172-2 173-2 175-2 178-2 182-2 183-2

Trench ..................... 25 25 11 11 11 11 11 12 12

Rock classification:

Altered volcanic ............ - - - - - - - - -

Clay ........................ - -

Dolomite .................... - - C C C _ _ C

Gossan ......................- -

Limestone ........ ...... _ _ _ C _

Shale ....................... - - - C _ _ C _ _ 

Springs deposit ............. C C -

Mineral:

Albite ......................

Andesine ....................

Augite ......................

Biotite .....................

Calcite ..................... - - A S F F _ A S

Carbon ...................... - -

Chlorite .................... - - A A S _ Cinnabar .................... T - M

Dolomite . ...... _ M P _ P P _ _ P

Illite ...................... P P A _

Kaolin minerals ............. S

K-feldspar ........ ..........

Limonite . ...... _ S F S _ F M F Magnetite ...................

Mesitite ....................

Muscovite .................. T

Pyrite ..................

Quartz ...................... P P T A

Sanidine ....................

Siderite ...... ...............

Sample

186-2 187-2 189-2 190-2 192-2 193-2 195-2 196-2 200-2

Trench ........................ 12 12 13 13 13 13 20 21 6

Rock classification:

Altered volcanic ............ - - - C - - - C -

Clay . ........ _

Dolomite .................... C C _ C C _ _ C

Gossan .................... - -

Limestone ................... -

Shale ....................... - - C C _ C

Springs deposit ............. - - - -

Mineral:

Albite ...................... - - - - - - - - -

Andesine .................... - - - - - - - - -

Augite ...................... - - - - - - - - -

Biotite ..................... - - - - - - - - -

Calcite ..................... M A S A - A S A F Carbon ......................

Chlorite .................... - A A _ A _ A _ Cinnabar .................... F

Dolomite .................... P P _ p P S T P Illite ...................... _ P _ A _ P _ _ 

Kaolin minerals .............

K-feldspar ..................

Limonite . ...... _ T _ A M T _ A _ Magnetite ................... - - - - - - - - -

Mesitite .................... - - - - - - - - -

Muscovite ................... - - - - - - - - -

Pyrite . . . .- - - - - - - -

Quartz ...................... - - - M - - - - -

Sanidine .................... - - - _ - - - A -

Siderite ....................
61

Sample

201-2 205-2 206-2 209-2 209T-2 211-2 213-2 215-2 218-2

Trench ...... ................ 6 7 7 19 20 20 7 26 23

Rock classification:

Altered volcanic ........... _ C - C - C - - -

Clay ....................... - - C _ _ 

Dolomite ................... - - C _ C C

Gossan ..................... _ _ 

Limestone .................. C -

Shale ...................... - - - - C _ _ _ -

Springs deposit ............ _ _ _ _ _ _ _ _ _ 

Mineral:

Albite ..................... _ _ _ _ _ _ _ _ _ 

Andesine ................... _ _ _ _ _ _ _ _ _ 

Augite ..................... _ _ _ _ _ _ _ _ _ 

Biotite .................... _ _ _ _ _ _ _ _ _ 

Calcite .................... P A A S A A T - F

Carbon ..................... _

Chlorite ................... S A S A _ A

Cinnabar ................... - - T _

Dolomite ................... - - A M M _ P P

Illite ..................... - - P A _ _ 

Kaolin minerals ............ _ _ P

K-feldspar ................. _ _ 

Limonite ................... _ A M A _ S M _ S

Magnetite .................. _ _ _ 

Mesitite ................... _ _ _ 

Muscovite .................. - - - P

Pyrite ..................... _ _ _ 

Quartz ..................... F - - _ S S M

Sanidine ................... A A A _ _ 

Siderite ... . _ _ _ _ _ _ _ _

________ ________ Sam ple

220-2 224-2 225-2 225A-2 226-2 226A-2 227A-2 228-2 228A-2

Trench .......... 23 23 23 30 23 30 30 23 30

Rock classification:

Altered volcanic ........ - - - C - - - - -

Clay .................... _

Dolomite ................ C C C - C C C C C

Limestone ............... _ _ 

Shale ................... _ _ 

Springs deposit ......... - - C

Mineral:

Albite .................. _ _ _ _ _ _ 

Andesine ................ - - - - - - T _ _ 

Augite .................. _ _ _ _ _ _ 

Biotite ................. _ _ _ _ _ _ 

Calcite ................. M S - - A M _ F _

Carbon .................. _

Chlorite ................ S

Cinnabar ................ S A S _ T P P T S

Dolomite ................ P P A _ P A S P A

Illite .................. - - - p

Kaolin minerals ......... - - - - -

K-feldspar .............. _ _ _ _ _ 

Limonite ................ - - - - - A S F A

Magnetite ............... _ _ _ _ _ _ _ _ _ 

Mesitite ................ _ _ _ _ _ _ _ _ _ 

Muscovite ............... _ _ _ _ _ _ _ _ _ 

Pyrite .................. _ _ _ _ _ _ _ _ _ 

Quartz .................. T - P - S - - - A

Sanidine ................

Siderite ................ ___ _ _ _ _ _ _ _
62

Sample

229A-2 230A-2 231A-2 232-2 234-2 237-2 238-2 239-2 240A-2 Trench .................... 30 30 30 30 30 30 30 30 30 Rock classification:

Altered volcanic .C C C C C - - C C Clay .................... - - - - - Dolomite ................ - - - - - C

Gossan .................. - - -_ _ _ Limestone ............... - - - - - - C

Shale ......- ............ _ - -_ _ _ Springs deposit ......... - - - - - - - Mineral:

Albite ....... ,.,.,.. - - -_ _ _ _ Andesine_ ................ - - -_ _ _ _ Augite .... .............. _ _ - _ _ Biotite ................. P p -_ _ _ _ Calcite ................. _ S A A - P A Carbon .... .............. - M _ Chlorite 

Cinnabar 

................ 

................ A A A P A S _ _ M F T T Dolomite ................ P

Illite ..................

Kaolin minerals ......... . _ _ _ 

K-feldspar ..............

Limonite .A S S S S S T M Magnetite ............... Mesitite ............... S Muscovite .............. A- A A _ S _ A A Pyrite .................. - - T T T Quartz .................. - -

Sanidine ....... ....... _ _ A A A P Siderite ._ _ _ _ _ . S

Sample

240B-2 91-3 92-3 93-3 94-3

Trench .30 51 52 42 41

Rock classification:

Altered volcanic .C - - - - Clay.- - - - - Dolomite .- - C - - Gossan .- - - - - Limestone .- C - - - Shale .- - - C C

Springs deposit ......... - - - - - Mineral:

Albite.- - - - - Andesine.- - - - - Augite .- - - - - Biotite ._ - - - - Calcite. A P - S M

Carbon ._ _ _ _. Chlorite ................ - A T P P

Cinnabar ._ _ _ _. Dolomite . - P _ T

Illite .- S T A A

Kaolin mineralse.. . _ _ K-feldspar .- _ _ _. Limonite ................ S M T _ F Magnetite .- - - _ Mesitite .- - - _ Muscovite ............... A - - _ Pyrite .T - - _ Quartz ........ .......... S

Sanidine .A . _ _ _ Siderite ._ _ _ _.
63

APPENDIX C.--LOGS OF DIAMOND-DRILL HOLES

The detailed logs of drillholes are arranged in chronological order of

drilling. Hole location coordinates and collar elevations were determined by

transit, chain, and stadia surveys. The original bearing of the traverse was

a compass bearing between two semipermanent hubs near the airstrip and drillhole 1; the original elevation was based on interpolation from a Geological

Survey map (4). The hole drilling dates are for elapsed time from the date

the hole started to completion date including Sundays (none worked), and also

include maintenance work on drill and accessory equipment that was necessary

while a hole was in progress. Holes 6, 7, and 13 were BX size; all others

were AX size, except for a short BX interval at the start. The column "C"

stands for chemical and "P" for petrographic analyses. Sample numbers listed

under these columns are in chronological number by year; that is, 7-1 means

sample 7 taken in 1961, while 7-2 means sample 7 taken in 1962. Analyses of

samples listed in the columns are found with the logs or in appendix D or E.

Holes 1 to 8 were drilled in 1961, holes 9 to 14 in 1962. The core interval

sampled does not always coincide with the drill run; the core was sampled when

mineralization occurred. In calculating assays for the entire run as found in

appendix D that section of core not assayed was assumed to contain no mercury.

Diamond-drill hole 1

Location: N 9,705.5, E 11,102.0 Date begun: June 23, 1961

Elevation of collar: 2,098.9 Date finished: June 27, 1961

Depth: 149.3 feet Core sizes: 0.0 - 13.0, BX

Dip: -44023' 13.0 - 149.3, AX

Bearing: S 76013' W

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

______ ______ percen t__ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

0.0 5.0 5.0 100 _ - Overburden of brown, broken _

dolomite.

5.0 9.5 4.5 62 _ - Black, broken dolomite, par- _

tially cemented with yellow,

friable dolomite, few small

quartz stringers and considerable iron stain.

9.5 11.6 2.1 85 _ - Same as 5.0 to 9.5 feet, but _

more iron stain.

11.6 13.0 1.4 36 _ - Broken and shattered siliceous _

tan dolomite, fractures partially filled with soft, yellow, friable dolomite, minor

iron stain.

13.0 14.0 1.0 90 _ Dark gray, cherty, recementeddolomite, iron stain.

14.0 16.8 2.8 86 _ - Dark gray, dense dolomite, -

minor iron.
64

Diamond-drill hole 1--Continued

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

percent

16.8 21.1 4.3 33 - - Broken, gray dolomite, limonite -

stain.

21.1 29.2 8.1 38 - - Medium gray dolomite, minor -

limonite.

29.2 29.9 .7 86 - - Medium gray dolomite, shattered, _

recemented.

29.9 39.4 9.5 79 - - Medium gray dolomite, soft yel- -

low dolomite on fractures, few

calcite stringers, minor iron

stain.

39.4 39.5 .1 100 - - Limestone, light and dark gray, _

thin alternating beds, folded

and deformed.

39.5 41.6 2.1 100 - - Same as 29.9 to 39.4 feet ....... ,

41.6 43.7 2.1 100 - - Medium to light gray dolomite,

much iron stain.

43.7 44.3 .6 100 - - Light gray, soft, thin-bedded -

limestone, limonite coating on

bedding planes which are 450

to axis of core.

44.3 49.6 5.3 47 - - Gray, broken, soft dolomite, -

much limonite coating on

fractures.

49.6 55.0 5.4 29 - - Light gray, fairly soft dolomite -

with a few vugs, yellow dolomite coating on fractures.

55.0 55.5 .5 100 1-1 - Gray, hard, cherty dolomite .0.10

55.5 58.2 2.7 19 2-1 - Medium to dark gray, hard, .22

cherty dolomite, few small

blebs cinnabar.

58.2 63.2 5.0 30 3-1 - Dark gray dolomite with dark .07

brown angular inclusions of

limonitic dolomite giving it

the appearance of conglomerate,

vuggy.

63.2 68.2 5.0 30 4-1 - Light gray dolomite, broken, .10

cherty, limonite coating on

fracture surfaces.

68.2 69.2 1,0 100 5-1 . .. ............ do .. ., .. . . 14

69.2 74.9 5.7 75 - - Medium to light gray, fine- -

grained dolomite, broken, minor

limonite.

74.9 75.2 .3 75 6-1 - Medium gray to yellow dolomite, .70

brecciated, slightly vuggy, few

small lenses of cinnabar.
65

Diamond-drill hole 1--Continued

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

percent -

75.2 76.2 1.0 84 - - Same as 74.9 to 75.2 feet, but -

no cinnabar.

76.2 76.5 .3 84 7-1 . ............... do .... .... 0..01

76.5 81.8 5.3 84 - - Light gray dolomite with an -

occasional small inclusion of a

darker gray dolomite, minor

limonite.

81.8 83.8 2.0 84 8-1 - Light gray dolomite, broken, .01

brecciated, much limonite.

83.8 86.0 2.2 90 - - Light gray dolomite, broken, -

slightly harder than previous

core.

86.0 86.4 .4 100 9-1 - Medium gray dolomite, no .005

mineralization.

86.4 87.0 .6 95 - - Medium gray dolomite, much red -

limonite.

87.0 88.5 1.5 95 10-1 . . do .. ....... .005

88.5 88.9 .4 95 11-1 - Medium gray dolomite, much red .65

limonite, few small blebs

cinnabar.

88.9 92.7 3.8 95 - - Medium gray dolomite, minor red -

limonite.

92.7 92.9 .2 100 - - Gray dolomite, tan che rtr........

92.9 93.3 .4 95 - - ............. do ....

93.3 95.2 1.9 95 - - Tan chert, gray dolomite..._

95.2 97.5 2.3 95 - - Gray dolomite, minor red

limonite.

97.5 104.0 6.5 94 - - Tan dolomite, red limonite ......

104.0 104.7 .7 94 12-1 - Tan dolomite, red limonite, .01

broken.

104.7 106.5 1.8 90 - - Tan dolomite, red limonite ...... -

106.5 107.0 .5 87 13-1 - Yellow, soft dolomite, limonite .01

stringers.

107.0 108.4 1.4 87 - - Tan dolomite, red limonite, -

broken.

108.4 111.8 3.4 87 - - Medium to light gray dolomite ... -

111.8 112.3 .5 87 14-1 - Medium to light gray dolomite .42

with one 1/16-inch stringer

cinnabar and few small 1/16-

inch-diameter blebs cinnabar.

112.3 118.5 6.2 90 - - Medium gray dolomite ............ ,

118.5 120.0 1.5 100 15-1 - Yellow to gray dolomite, very .05

small quartz stringers.

120.0 120.5 .5 100 16-1 - Same as 118.5 to 120.0 feet, .43

but with small blebs of

cinnabar.
66

Diamond-drill hole 1--Continued

Length, Core Sam le Percent

From To feet recovery, C P Description mercury percent

120.5 125.7 5.2 95 - Light to medium gray dolomite, _

broken from 122.9 to 125.7

feet.

125.7 127.0 1.3 83 - - Medium gray dolomite with dark _

gray bands of shale.

127.0 129.3 2.3 83 - - Light gray dolomite, 0.5-foot- -

long inclusion of shale parallel to long axis at 128 feet.

129.3 139.5 10.2 16 17-1 - Light and dark gray dolomite, 0.01

broken at 129.3 and 129.6 feet,

dolomite has a platy structure.

139.5 149.3 9.8 18 18-1 - Light gray dolomite, broken, <.005

last 0.5 foot is cherty and ___________ ________ _ semibrecciated.

Diamond-drill hole 2

Location: N 9,757.2, E 10,228.2 Date begun: July 5, 1961

Elevation of collar: 2,113.4 Date finished: July 10, 1961

Depth: 140 feet Core sizes: 0.0 - 16.5, BX

Dip: -60° 16.5 - 140.0, AX

Bearing: N 830521 E

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

percent

0.0 11.1 11.1 50 _ - Yellow dolomite, broken, fria--

ble, minor limonite.

11.1 15.4 4.3 100 _ Light yellow dolomite, vuggy,-

with some dark yellow iron

stain on vugs.

15.4 33.6 18.2 92 _ - Light gray dolomite, fairly -

soft.

33.6 35.8 2.2 100 19-1 - Gray and yellow dolomite, very 0.03

vuggy, small quartz crystals

and sulphur in vugs.

35.8 36.1 .3 100 - - Medium gray dolomite .- 36.1 36.8 .7 100 20-1 - Dark gray dolomite, vuggy, .06

occasional bleb of cinnabar.

36.8 37.2 .4 100 21-1 - Same as 36.1 to 36.8 feet, but .45

with a 1/4-inch lens of

cinnabar in vug. 37.2 37.5 .3 100 22-1 - Gray dolomite, blebs cinnabar.. .02

37.5 39.2 1.7 100 23-1 - Medium gray dolom ite .04

39.2 43.5 4.3 80 - - Medium gray dolomite, fairly -

soft.
67

Diamond-drill hole 2--Continued

Length, Core Samp le Percent

From To feet recovery, C P Description mercury

percent C __

43.5 44.3 0.8 80 24-1 - Light gray to yellow dolomite, 1.95

small lens of cinnabar.

44.3 45.2 .9 80 - - Medium gray dolomite, hard, -

minor limonite coating on

fracture planes.

45.2 46.0 .8 80 25-1 - Gray dolomite, small lens of .45

cinnabar.

46.0 51.3 5.3 84 - - Medium gray dolomite,brokenwith -

dark brown angular inclusions

of limonitic dolomite similar

to 58.2 to 63.2 feet in hole 1.

51.3 52.4 1.1 91 26-1 - Dark gray dolomite, vuggy, small 2.19

lens of cinnabar, minor amount

broken, siliceous dolomite.

52.4 63.2 10.8 75 - - Light gray to light tan dolo- -

mite, few vugs.

63.2 68.3 5.1 50 27-1 - Dark gray dolomite, cherty...... .03

68.3 69.3 1.0 40 28-1 - Dark gray dolomite, cherty, .01

broken.

69.3 76.7 7.4 5 - - Black dolomite, broken, limonite -

coating on fracture surfaces.

Sludge = 0.08 percent Hg.

76.7 80.0 3.3 9 - - Dark gray dolomite, siliceous, -

indications are it is vuggy,

broken. Sludge= 0.05 percent Hg.

80.0 89.1 9.1 35 29-1 - Medium gray dolomite, broken, .05

siliceous, and abrasive.

Sludge = 0.13 percent Hg.

89.1 89.4 .3 77 - - Medium gray dolomite ............ ,

89.4 90.6 1.2 100 30-1 - Light gray dolomite, very vuggy, .01

occasional dark brown limonite

stringer.

90.6 99.3 8.7 75 - - Light gray dolomite, occasional -

dark brown limonite stringer.

99.3 102.7 3.4 33 31-1 - Light gray dolomite, much .01

limonite.

102.7 109.4 6.7 33 32-1 - Dark gray dolomite, broken, .005

limonite coating on fracture

surfaces.

109.4 109.7 .3 100 32A-1 - Dark gray dolomite, small lens .03

cinnabar.

109.7 120.0 10.3 60 33-1 - Dark gray dolomite, broken .. 005

120.0 130.0 10.0 26 34-1 _. ...... do . . ....... .005

130.0 140.0 10.0 15 35-1 - Very dark gray dolomite, dark .005

brown limonite coating on frac-

_ tures. Sludge= 0.02 percent Hg.1
68

Diamond-drill hole 3

Location: N 9,781.5, E 10,205.2 Date begun: July 15, 1961

Elevation of collar: 2,115.2 Date finished: July 21, 1961

Depth: 143 feet Core sizes: 0.0 - 8.2, BX

Dip: -47°07' 8.2 - 143.0, AX

Bearing: S 66003' W

Length, Core Sam le Percent

From To feet recovery, C P Description mercury - - _______ percent I i_ _ _ _ _ __ _ _ _ __p _ _ __ _ _ _

0.0 5.0 5.0 100 - - Overburden...... *............. _.

5.0 8.2 3.2 100 - - Light gray dolomite ............. _ 8.2 10.1 1.9 96 - - Gray dolomite, soft, minor -

limonite.

10.1 10.4 .3 96 - - Gray dolomite, broken, much tan -

limonite.

10.4 38.2 27.8 77 - - Medium to light gray dolomite ... -

38.2 38.8 .6 100 - - Light gray dolomite, vuggy...... -

38.8 39.3 .5 100 - - Light gray dolomite ............. _ 39.3 40.5 1.2 100 - - Light gray dolomite, few vugs -

and minor limonite.

40.5 43.1 2.6 100 - - Light gray dolomite ............ . -

43.1 48.4 5.3 72 - - Gray dolomite, broken, brec- -

ciated, few small vugs.

48.4 58.0 9.6 33 - - Light cream to gray dolomite, -

broken, brecciated, minor

limonite.

58.0 66.7 8.7 100 - - Light gray dolomite, slightly -

brecciated, minor limonite.

66.7 67.8 1.1 100 - - Gray dolomite, reddish limonite. -

67.8 78.0 10.2 100 - - Same as 66.7 to 67.8 feet, but -

more limonite and a few vugs.

78.0 88.0 10.0 40 - - Light and dark gray dolomite, -

broken.

88.0 92.5 4.5 24 - - Light gray dolomite, broken ..... -

92.5 113.0 20.5 4 - - Dark gray dolomite, broken...... -

113.0 116.0 3.0 1.5 - - Light gray dolomite, broken. -

116.0 126.0 10.0 0 - - No core, no mercury in sludge... -

126.0 136.8 10.8 10 - - Gray dolomite, broken........... -

136.8 142.8 6.0 31 - - Tan dolomite, broken, consider- -

able limonite.

142.8 143.0 .2 100 - - Dark yellowish gray shale, -

broken. Note: Negative mercury assay for all of hole 3

_______ _ sludges.
69

Diamond-drill hole 4

Location: N 9,718.0, E 10,158.5 Date begun: July 25, 1961

Elevation of collar: 2,118.4 Date finished: August 1, 1961

Depth: 150.2 feet Core sizes: 0.0 - 19.5, BX

Dip: -46°39' 19.5 - 150.2, AX

Bearing: N 77034' E

Length, Core Sam lPercent

From To feet recovery, C P Description mercury

percent _ _

0.0 10.0 10.0 0 - - Overburden .. ........ ............. _

10.0 12.0 2.0 55 36-1 - Gray dolomite, brown chert, 0.01

broken.

12.0 12.3 .3 67 37-1 - Light gray dolomite, much .005

limonite.

12.3 14.5 2.2 32 38-1 - Light yellow dolomite, broken, .22

friable,small lens of cinnabar.

14.5 14.9 .4 88 39-1 - Light yellow to gray dolomite ... <.005

14.9 15.4 .5 100 40-1 - Light yellow to gray dolomite, <.005

small blebs of cinnabar.

15.4 16.7 1.3 100 41-1 - Light yellow to gray dolomite... .005

16.7 19.5 2.8 100 42-1 - Deep yellow dolomite, broken, .16

soft, friable, few small blebs

cinnabar.

19.5 21.5 2.0 53 - - Yellow dolomite with a few small -

inclusions of black dolomite,

appears to have been recemented, soft, and friable.

21.5 22.4 .9 100 43-1 - Dark gray to yellow dolomite, .05

brecciated, limonite stringers.

22.4 22.8 .4 88 44-1 - Same as 21.5 to 22.4 feet, with 1.60

small blebs cinnabar.

22.8 23.1 .3 100 45-1 - Same as 21.5 to 22.4 feet, with .18

no visible cinnabar.

23.1 29.5 6.4 53 - - Light gray dolomite with a yel- -

low cast, broken.

29.5 33.6 4.1 100 46-1 - Light gray to yellow dolomite .07

with occasional small bleb

cinnabar.

33.6 35.0 1.4 97 - - Light gray to yellow dolomite ... -

35.0 44.2 9.2 66 - - Yellow dolomite, broken ......... ,

44.2 55.0 10.8 45 47-1 - Yellow dolomite, broken, brec- .01

ciated, occasional small piece

of black dolomite, minor amount

gray dolomite, brecciated.

55.0 69.7 14.7 38 48-1 - Dark gray dolomite with shale .005

inclusions, broken.

69.7 80.0 10.3 60 49-1 - Light yellow dolomite, broken, .01

few vugs.

80.0 90.6 10.6 42 - - Medium to light gray dolomite, -

broken.
70

Diamond-drill hole 4--Continued

Length, Core Sample Percent

From To feet recovery, C P Description mercury

percent _

90.6 93.0 2.4 100 50-1 - Gray to yellow dolomite, with <0.005

inclusions of dark gray dolomite, limonite.

93.0 103.0 10.0 40 51-1 - Gray to black dolomite, vuggy, .01

abrasive,much limonite, broken.

103.0 110.5 7.5 24 52-1 Gray to brownish dolomite, .11

broken, much limonite.

110.5 130.5 20.0 93 - - Light gray to yellow dolomite, -

brecciated, foliated.

130.5 140.5 10.0 9 53-1 - Gray to yellow dolomite, broken, .01

cherty, limonite.

140.5 150.2 9.7 18 54-1- _Dark gray dolomite, broken .. 01

Diamond-drill hole 5

Location: N 9,653.0, E 10,225.4 Date begun: August 5, 1961

Elevation of collar: 2,102.7 Date finished: August 7, 1961

Depth: 40 feet Core sizes: 0.0 - 2.5, BX

Dip: -31°03' 2.5 - 40.0, AX

Bearing: S 860331 W

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

percent I

0.0 2.5 2.5 44 55-1 - Dark gray dolomite, broken, very 0.06

hard.

2.5 12.5 10.0 2 56-1 - Dark gray dolomite, broken, very .01

hard. Sludge = 0.04 percent Hg.

12.5 15.0 2.5 8 57-1 - Dark gray dolomite, broken, very .02

hard. Sludge = 0.03 percent Hg.

15.0 16.5 1.5 73 58-1 - ............. do................. .02

16.5 19.5 3.0 100 59-1 - Dark gray dolomite, broken, very <.005

hard. Sludge = 0.01 percent Hg.

19.5 23.5 4.0 8 60-1 - Dark gray dolomite, broken, very <.005

hard. Sludge = 0.03 percent Hg.

23.5 27.5 4.0 12 61-1 - .............. do . ........... .03

27.5 31.9 4.4 10 62-1 - Dark gray dolomite, broken, very .01

hard. Sludge = 0.04 percent Hg.

Minor amount of light yellow

chert.

31.9 40.0 8.1 62 63-1 - Yellow dolomite, soft, friable, .005

hole ended in what is probably

a large underground cavern.

Strong blast of air blew from

the collar of this hole for 2

days after the cavern was

p penetrated.
71

Diamond-drill hole 6

Location: N 9,712.3, E 10,255.2 Date begun: August 8, 1961

Elevation of collar: 2,100.7 Date finished: August 9, 1961

Depth: 31.5 feet Core sizes: 0.0 - 31.5, BX

Dip: -24°18'

Bearing: N 38047' W

Length, Core Samp le Percent

From To feet recovery, C P Description mercury

percent _

0.0 10.0 10.0 0 _ - Overburden, sludge ...................... _

10.0 13.0 3.0 0 _ No core, sludge ......................... _

13.0 14.5 1.5 73 64-1 - Dark gray dolomite, very hard, broken, 0.20

few small shale inclusions, very few

small blebs cinnabar.

14.5 19.8 5.3 47 65-1 - Gray dolomite, broken, very hard, few .10

shale inclusions.

19.8 22.8 3.0 37 66-1 - Gray dolomite, porous, broken, few small .57

lenses cinnabar.

22.8 25.5 2.7 22 67-1 - Light gray, porous dolomite ............. .12

25.5 27.0 1.5 40 68-1 - Light gray, porous dolomite, small blebs .23

cinnabar.

27.0 31.5 4.5 93 69-1 - Light gray, porous dolomite to 29.2 .04

feet, from 29.2 to 31.5 feet, yellow

____ _______ ________ _ dolomite, soft, friable. I

Diamond-drill hole 7

Location: N 9,725.6, E 10,255.2 Date begun: August 10, 1961

Elevation of collar: 2,104.0 Date finished: August 15, 1961

Depth: 25 feet Core sizes: 0.0 - 25.0, BX

Dip: Vertical

Bearing: --

Length, Core Sample Percent

From To feet recovery, C P Description mercury

percent _

0.0 5.0 5.0 0 _ - No core. Sludge = 3.04 percent Hg ...... ,

5.0 8.5 3.5 0 _ _ No core. Sludge = 4.32 percent Hg .-

8.5 12.0 3.5 6 70-1 - Gray dolomite, hard, brittle, broken, -

small lens of cinnabar. Core sample

lost. Sludge = 5.13 percent Hg.

12.0 13.5 1.5 33 71-1 - Gray dolomite, porous, broken lens of 3.38

cinnabar. Sludge = 1.95 percent Hg.

13.5 16.0 2.5 5 - - Gray dolomite, chert, lens cinnabar. -

Sludge = 6.53 percent Hg.

16.0 17.5 1.5 5 - - Same as 12.0 to 13.5 feet. Sludge = _

3.55 percent Hg.

17.5 21.5 4.0 2 - - Gray dolomite, porous, hard, cherty. _

Sludge = 10.98 percent Hg.

21.5 24.0 2.5 0 - - Sludge = 2.69 percent Hg .

24.0 25.0 1.0 0 - - Sludge = 0.56 percent Hg. Bottom of _

II_ I _I I_ hole is apparently all broken chert.
72

Diamond-drill hole 8

Location: N 9,700.8, E 10,263.3 Date begun: August 17, 1961

Elevation of collar: 2,099.8 Date finished: August 24, 1961

Depth: 203.7 feet Core sizes: 0.0 - 7.0, BX

Dip: -73042' 7.0 - 203.7, AX

Bearing: N 67018' W

Length, Core Sample Percent

From To feet recovery, C P Description mercury

percent _

0.0 7.0 7.0 0 - - Overburden . .................. _

7.0 13.0 6.0 100 72-1 - Gray to yellow dolomite, few 0.03

vugs.

13.0 15.5 2.5 80 73-1 - Gray to yellow dolomite ........ <.005

15.5 19.5 4.0 100 74-1 . .... do ...... 01

19.5 24.5 5.0 100 75-1 - Light gray to yellowish gray <.005

dolomite.

24.5 28.8 4.3 94 76-1 - Light gray dolomite, minor <.005

amount of yellow dolomite,

few vugs.

28.8 29.5 .7 94 77-1 - Light gray dolomite, small .35

lens cinnabar.

29.5 30.3 .8 98 78-1 . do ..... 13

30.3 31.2 .9 98 79-1 - Medium gray dolomite, minor .02

limonite coating.

31.2 31.5 .3 100 80-1 - Medium gray dolomite, small 1.52

blebs cinnabar.

31.5 34.5 3.0 98 81-1 - Medium gray dolomite, broken, <.005

vuggy.

34.5 37.7 3.2 63 82-1 - Light gray dolomite, very hard, .01

broken.

37.7 42.5 4.8 100 83-1 - Medium gray dolomite, much .01

limonite coating.

42.5 49.2 6.7 100 - - Medium gray to yellow dolomite, _

broken, few vugs, minor

limonite.

49.2 49.8 .6 100 84-1 - Light yellow to gray dolomite, <.005

soft, vuggy, few small blebs

cinnabar.

49.8 55.1 5.3 75 - - Medium to light gray dolomite, -

minor limonite.

55.1 56.0 .9 90 85-1 - Light gray dolomite, hard, few <.005

vugs, small blebs cinnabar.

56.0 61.6 5.6 95 - - Light gray dolomite, minor -

limonite.

61.6 62.7 1.1 100 86-1 - Light gray dolomite, single .005

small bleb cinnabar.

62.7 64.5 1.8 95 87-1 - Greenish yellow dolomite, soft, .005

broken.

64.5 66.0 1.5 93 88-1 . ............... do.. ....... .005
73

Diamond-drill hole 8--Continued

Length, Core Sam e Percent

From To feet recovery, C P Description mercury

percent

66.0 70.5 4.5 100 - - Gray dolomite, much limonite... -

70.5 74.0 3.5 100 89-1 - Greenish yellow dolomite, soft, .01

broken.

74.0 80.0 6.0 100 90-1 .. do .............. .005

80.0 83.5 3.5 75 91-1 - Yellow to gray dolomite, much .005

limonite.

83.5 89.3 5.8 85 92-1 - Gray to yellow dolomite, .005

broken.

89.3 91.5 2.2 100 93-1 - Light yellow dolomite, broken, .01

occasional bleb of cinnabar.

91.5 91.9 .4 100 94-1 - Light yellow dolomite, broken, .11

small blebs cinnabar.

91.9 93.5 1.6 100 95-1 - Light yellow dolomite, broken, .14

limonite, occasional bleb

cinnabar.

93.5 98.0 4.5 90 96-1 - Dark brown, limonite-stained .25

dolomite, small lens of

cinnabar at 97 feet.

98.0 98.5 .5 90 97-1 - Light gray dolomite, broken.... .16

98.5 99.0 .5 100 98-1 . .......... ... ,.do ............. . .07

99.0 103.3 4.3 23 99-1 . .... do ......... .02

103.3 104.0 .7 43 100-1 - ........ do .............. .13

104.0 108.0 4.0 75 101-1 - Light gray dolomite, broken, .02

dark gray angular inclusions

of dolomite.

108.0 117.0 9.0 22 102-1 - Light gray dolomite............ .02

117.0 118.6 1.6 100 103-1 - Light gray dolomite, vuggy, .02

limonite coating on fracture

surfaces, broken, 117.0 to

117.5 feet, dark gray

dolomite.

118.6 119.6 1.0 100 104-1 - Light gray dolomite, much .02

limonite.

119.6 121.3 1.7 100 105-1 - Light gray to yellow dolomite, .005

fine-grained, limonite stain.

121.3 123.8 2.5 91 106-1 - Yellow to gray dolomite, soft .01

(almost mud-like in places),

limonite lens.

123.8 125.0 1.2 100 107-1 - Light gray dolomite. ..... .01

125.0 128.0 3.0 100 108-1 - Light gray dolomite, soft .93

(mud-like), numerous limonite

stringers.

128.0 138.0 10.0 46 109-1 - Light gray dolomite, broken, .01

much limonite.

138.0 148.0 10.0 20 110-1 - Same as 128.0 to 138.0, but .01

minor limonite.
74

Diamond-drill hole 8--Continued

Length, Core Samp le Percent

From To feet recovery, C P Description mercury

percent

148.0 157.9 9.9 40 111-1 - Light gray dolomite, broken, <0.005

minor limonite.

157.9 167.8 9.9 47 112-1 - Light gray dolomite, broken, .005

much limonite.

167.8 177.9 10.1 100 113-1 - Light gray dolomite, trace <.005

limonite.

117.9 185.0 7.1 70 114-1 - Light gray dolomite, trace .005

limonite, broken.

185.0 192.0 7.0 71 115-1 - Light gray dolomite, no iron, -

broken.

192.0 203.7 11.7 90 116-1 - Light gray dolomite.......... .005

Diamond-drill hole 9

Location: N 11,357.9, E 11,357.9 Date begun: June 7, 1962

Elevation of collar: 2,199.4 Date finished: June 11, 1962

Depth: 110.5 feet Core sizes: 0.0 - 8.8, BX

Dip: -45° 8.8 - 110.5, AX

Bearing: S 790 W

Length, Core Samp le Percent

From To feet recovery, C P Description mercury

percent I

0.0 7.4 7.4 0 - - Overburden ...... .......... _ 7.4 8.8 1.4 79 1-2 - Black limestone, small cal- <0.01

cite stringers, minor amount

medium gray, porous sandstone, limonite.

8.8 9.9 1.1 91 2-2 - Same as 7.4 to 8.8 feet, but .01

more iron, and more

siliceous.

9.9 13.0 3.1 35 3-2 3-2 Black limestone,fine-grained, .01

small calcite stringers,

minor limonite.

13.0 15.0 2.0 75 4-2 - Dark gray, sandy limestone, <.01

thin bedded, small fault

gouge stringer at 14.0 feet,

is 600 to long axis of core.

15.0 19.2 4.2 29 5-2 - Dark gray to black limestone, .01

calcite stringers, minor

limonite, broken.

19.2 23.2 4.0 93 6-2 - Same as 15.0 to 19.2 feet, .01

not as broken.

23.2 28.5 5.3 40 7-2 7-2 Black, sandy, thin-bedded .01

shale, black limestone,

limonite stain.
75

Diamond-drill hole 9--Continued

Length, Core Sam le Percent

From To feet recovery, C Description mercury

_____ ~percent __ _

28.5 35.6 7.1 50 8-2 - Gray to dark gray to black <0.01

limestone, calcite

stringers, yellow limonite,

broken.

35.6 36.3 .7 86 9-2 - Dark gray to yellow dolomite, <.01

fractured.

36.3 38.3 2.0 100 10-2 - Same as 35.6 to 36.3 feet, .12

but with a rough texture,

few blebs cinnabar (Note:

Section from 37.1 to 37.5

feet removed and reported

in sample 11-2).

11-2 11-2 Same as 35.6 to 36.3 feet, 3.09

but with more blebs

cinnabar.

38.3 38.8 .5 80 12-2 - Gray to yellow dolomite ...... .01

38.8 40.0 1.2 17 13-2 - Blue clay fault gouge ........ <.01

40.0 40.6 .6 100 14-2 - Yellow to brown dolomite, .01

broken.

40.6 43.2 2.6 85 15-2 15-2 Light gray dolomite, hard, .02

siliceous, minor limonite,

few calcite stringers.

43.2 50.6 7.4 15 16-2 - Light gray to yellow dolo- <.01

mite, broken.

50.6 55.6 5.0 96 17-2 - Gray to dark gray dolomite, <.01

hard, siliceous, numerous

calcite stringers.

55.6 58.2 2.6 81 18-2 18-2 Brown shale with few small <.01

inclusions of gray shale,

minor calcite and pyrite.

58.2 65.5 7.3 49 19-2 - Brown to light brown shale to <.01

60.2 feet. From 60.2 to

65.5 feet, gray, siliceous

dolomite with limonite

stain, minor calcite

stringers.

65.5 70.5 5.0 100 20-2 - Rusty limestone with gray <.01

patches, calcite stringers.

From 69.0 to 70.5 feet is

dark gray limestone.

70.5 75.5 5.0 88 21-2 21-2 Gray to dark gray limestone, <.01

brecciated, limonite veinlets give core a mottled

appearance, calcite stringers, foliation between 70.5

to 71.5 feet.
76

Diamond-drill hole 9--Continued

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

-ercent

75.5 80.5 5.0 50 22-2 22-2 Light gray, altered volcanic <0.01

or hydrothermal rock, small

green particles on blebs,

siliceous, broken, considerable limonite.

80.5 82.5 2.0 40 23-2 - Dark gray to black limestone, <.01

fine-grained, calcite

stringers, broken.

82.5 90.5 8.0 10 24-2 24-2 Black limestone, fine- .01

grained, broken.

90.5 95.5 5.0 18 25-2 - Black limestone, fine- <.01

grained, broken, vuggy near

90.5-foot end.

95.5 100.5 5.0 54 26-2 - Black limestone, fine- <.01

grained, broken, cherty,

minor calcite.

100.5 105.5 5.0 33 27-2 . ............. do... ......... . <.01

105.5 110.5 5.0 0 - - No core ....................... _

Diamond-drill hole 10

Location: N 11,353.1, E 11,401.5 Date begun: June 12, 1962

Elevation of collar: 2,199.5 Date finished: June 19, 1962

Depth: 121.0 feet Core sizes: 0.0 - 10.0, BX

Dip: -60° 10.0 - 121.0, AX

Bearing: S 790 W

Length, Core Samp le Percent

From To feet recovery, C P Description mercury

percent

0.0 10.0 10.0 0 - - No core . ......................

10.0 15.4 5.4 15 28-2 - Gray limestone, sandy, sili- <0.01

ceous, broken, limonite

stain, calcite stringers.

15.4 20.2 4.8 27 29-2 - Same as 10.0 to 15.4 feet, <.01

thin bedded.

20.2 25.4 5.2 54 30-2 - 20.2 to 21.0 feet is gray .01

limestone, sandy, thin bedded

(bedding planes 600 to long

axis), and light tan to gray

limestone with minor calcite

stringers. 21.0 to 25.4 feet

is gray to dark gray limestone, siliceous.

25.4 30.4 5.0 34 31-2 - Dark gray limestone, sili- <.01

ceous, broken calcite.
77

Diamond-drill hole 10--Continued

Length, Core Sample Percent

From To feet recovery, C P Description mercury

percent

30.4 35.4 5.0 34 32-2 32-2 From 30.4 to 32.9 feet, same <0.01

as 25.4 to 30.4 feet. From

32.9 to 35.4 feet, dark

gray to black phyllite

interbedded with dark gray

shale and limestone, a few

calcite stringers (between.

bedding), bedding 600 to

long axis, minor foliation

at 35.4 feet.

35.4 40.9 5.5 31 33-2 - Same as 25.4 to 30.4 feet... <.01

40.9 43.0 2.1 57 34-2 - Same as 36.3 to 38.8 feet in <.01

hole 9, or a dark gray to

yellow dolomite with a

rough surface or texture.

No cinnabar.

43.0 43.7 .7 57 35-2 - Gray to yellow dolomite, <.01

same as 38.3 to 38.8 feet

in hole 9.

43.7 45.4 1.7 71 36-2 - Dark gray to yellow dolo- <.01

mite, siliceous, broken,

calcite and quartz

stringers.

45.4 46.2 .8 75 37-2 - Light tan shale, siliceous.. <.01

46.2 49.5 3.3 75 38-2 38-2 Light gray shale, soft, <.01

shattered.

49.5 50.5 1.0 75 39-2 - Light tan shale, reddish <.01

cast, limonite.

50.5 55.5 5.0 71 40-2 40-2 Light gray to tan dolomite, <.01

siliceous, minor calcite

stringers, red chert at

53.5 feet.

55.5 58.8 3.3 79 41-2 - Rusty-gray, altered volcanic <.01

42-2 rock (43-2), broken at 58.0

43-2 to 58.2 feet, is a greenish

gray altered volcanic

(42-2) whose contact is 600

with the rusty-gray

volcanic.

58.8 65.8 7.0 92 44-2 44-2 Medium gray, altered vol- <.01

canic, greenish cast, hard,

small dark green

inclusions.
78

Diamond-drill hole 10--Continued

Length, Core Sam )le Percent

From To feet recovery, C P Description mercury percent

65.8 70.8 5.0 94 45-2 45-2 Light tan, altered volcanic <0.01

46-2 with small calcite inclusions and 1/16-inch-diameter dark gray angular

fragments. 45-2 at 70.8

feet has gradually changed

to a dark gray, hard, very

siliceous, altered volcanic (46-2).

70.8 75.8 5.0 94 47-2 47-2 Light tan to gray, altered <.01

47A-2 volcanic similar to 65.8

48-2 to 70.8 feet except

slightly more tan color,

shale fragments. 47-2 at

72.0 feet, 47A-2 shale

fragments, 48-2 at 75.0

feet.

75.8 80.2 4.4 57 49-2 - Light tan to gray, altered <.01

volcanic or hydrothermal

rock, calcite stringers,

very similar to 70.8 to

75.8 feet, minor limonite.

80.2 85.2 5.0 54 - 50-2 Gray to green, altered vol- -

canic, gradually grades

from very hard with no

pyrite at 80.2 feet to

softer with pyrite at 85.2

feet, 50-2 at 85.0 feet.

Similar to 70.8 to 75.8

feet.

85.2 90.2 5.0 57 51-2 51-2 Same as 80.2 to 85.2 feet, <.01

altered volcanic with both

hard and soft sections

both containing much

pyrite. End at 90.0 feet

is gray limestone with

calcite and pyrite.

90.2 91.5 1.3 100 52-2 52-2 Dark gray to black lime- <.01

stone, fine grained, minor

calcite and pyrite.

91.5 102.3 10.8 7 53-2 - Same as 90.2 to 91.5 feet, <.01

broken.

102.3 110.9 8.6 33 54-2 - .. do ............. <.01

110.9 116.3 5.4 54 55-2 - Dark gray limestone, thin- <.01

bedded, fine-grained.

116.3 121.0 4.7 53 56-2 - Black limestone, thin- <.01

bedded, fine-grained.
79

Diamond-drill hole 11

Location: N 11,355.4, E 11,396.0 Date begun: June 20, 1962

Elevation of collar: 2,200.5 Date finished: June 25, 1962

Dip: -30° Core sizes: 0.0 - 7.0, BX

Depth: 33.8 feet 7.0 - 33.8, AX

Bearing: S 310 W

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

percent I

0.0 7.0 7.0 0 - - Overburden..... _ .............. 

7.0 17.6 10.6 12 57-2 57-2 Black, limy dolomite, lime- <0.01

57A-2 stone, fine-grained, broken,

calcite stringers, tan

limonite (57A-2).

17.6 24.8 7.2 42 58-2 58-2 Black to dark gray limestone <.01

and shale, thin bedded,

calcite stringers, limonite,

broken.

24.8 29.8 5.0 46 59-2 - .............do...... <.01

29.8 31.8 2.0 35 60-2 - .. do.......do...........* <.01

31.8 33.8 2.0 15 61-2 - . ... do ....... <.01

Diamond-drill hole 12

Location: N 11,355.9, E 11,398.3 Date started: June 26, 1962

Elevation of collar: 2,200.2 Date finished: July 1, 1962

Depth: 112.8 feet Core sizes: 0.0 - 7.0, BX

Dip: -450 7.0 - 112.8, AX

Bearing: S 310 W

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

percent

0.0 7.0 7.0 0 - - Overburden, no core .......

7.0 15.8 8.8 8 62-2 - Black, sandy limestone, broken, <0.01

calcite stringers.

15.8 20.0 4.2 31 63-2 - .. ...... ...... do ............. <.01

20.0 25.8 5.8 57 64-2 64-2 Gray, black, tan, shale, banded, <.01

thin bedded (bedding 600 to

long core axis) minor foliation, calcite stringers.

25.8 35.5 9.7 69 65-2 - Gray to black limestone, sili- <.01

ceous, sandy, fine-grained,

calcite stringers, few tan

limonite stringers.

35.5 45.5 10.0 67 66-2 - Gray to dark gray, limy shale, <.01

thin bedded, minor foliation,

tan to yellow limonite.
80

Diamond-drill hole 12--Continued

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

percent

45.5 46.5 1.0 100 67-2 - Dark gray to black limestone, <0.01

fine-grained, siliceous,

calcite stringers.

46.5 48.6 2.1 100 68-2 68-2 Light gray dolomite, reddish <.01

cast, limonite, few calcite

stringers. From 46.5 to

46.6 feet is similar to

36.3 to 38.3 feet in hole 9.

48.6 55.5 6.9 5 - - Gray dolomite, broken, no _

core, sample sludge = 0.02

percent Hg.

55.5 60.0 4.5 36 70-2 70-2 Dark gray dolomite, broken, <.01

calcite, limonite, quartz.

60.0 72.8 12.8 0 - - No core. Sludge, 60.0 to _

66.8 feet - 0.02 percent Hg;

66.8 to 72.8 feet = <0.01

percent Hg.

72.8 78.8 6.0 16 71-2 - Dark gray to black, sandy <.01

limestone, small lens and

stringers calcite.

78.8 85.0 6.2 19 72-2 72-2 Dark gray to rusty hydrother- <.01

mal rock, vuggy, small

pyrite crystals, quartz,

minor limonite, broken.

85.0 95.8 10.8 28 73A-2 - Black to dark gray shale, <.01

small pyrite crystals, minor

calcite and limonite

stringers-, broken,

siliceous.

95.8 105.8 10.0 4 73-2 73-2 Dark gray shale, fine- <.01

grained, siliceous, broken,

calcite stringers. Sludge =

0.01 percent Hg.

105.8 112.8 7.0 32 74-2 - ....... .do .............. <.01
81

Diamond-drill hole 13

Location: N 11,398.3, E 11,397.2 Date begun: July 2, 1962

Elevation of collar: 2,211.1 Date finished: July 4, 1962

Depth: 35.0 feet Core sizes: 0.0 - 35.0, BX

Dip: -42°

Bearing: S 770 W

Length, Core Sample Percent

From To feet recovery, C Description mercury

percent I

0.0 6.0 6.0 0 - - Overburden, no core ...........

6.0 10.0 4.0 75 75-2 - Dark gray to black dolomite, <0.01

fine-grained, siliceous, calcite stringers, minor limonite coating on fractures.

10.0 15.0 5.0 44 76-2 76-2 Dark gray to black dolomite, .01

siliceous, calcite stringers,

considerable limonite.

15.0 20.3 5.3 66 77-2 - Same as 10.0 to 15.0 feet, but .01

with minor calcite and limonite, broken.

20.3 25.3 5.0 14 78-2 - Same as 10.0 to 15.0 feet with .01

79-2 - segments of light yellow,

soft dolomite, 72-2 is of

such a segment, broken.

25.3 30.0 4.7 26 80-2 80-2 Light gray to yellow dolomite, <.01

minor calcite stringers,

minor red chert.

30.0 35.0 5.0 48 81-2 - Light yellow dolomite with <.01

thin-bedded gray limestone,

minor calcite stringers,

_____ minor red chert.

Diamond-drill hole 14

Location: N 8,262.0, E 9,311.4 Date begun: July 19, 1962

Elevation of collar: 2,046.4 Date finished: July 28, 1962

Depth: 232.5 feet Core sizes: 0.0 - 6.0, BX

Dip: -80° 6.0 - 232.5, AX

Bearing: S 590 E

Length, Core Sample Percent

From To feet recovery, C P Description mercury

percent -

0.0 6.0 6.0 0 - - Overburden, no core ............. _

6.0 10.5 4.5 100 82-2 - Light gray dolomite, broken, 0.10

slightly vuggy, occasional

bleb cinnabar.

10.5 15.0 4.5 11 83-2 - Medium gray dolomite, broken, .10

siliceous.
82

Diamond-drill hole 14--Continued

Length, Core Sample Percent

From To feet recovery, C P Description mercury

percent _

15.0 20.6 5.6 9 84-2 - Light gray dolomite, yellow 0.14

dolomite. Sludge = 0.17 percent Hg.

20.6 25.6 5.0 74 85-2 85-2 Light gray dolomite, broken, .03

few vugs. Sludge = 0.11 percent Hg.

25.6 31.4 5.8 21 86-2 - Same as 20.6 to 25.6 feet. .01

Sludge = 0.02 percent Hg.

31.4 38.4 7.0 60 87-2 - Same as 20.6 to 25.6 feet, but .01

more vugs, occasional bleb

cinnabar.

38.4 43.8 5.4 5 - - Light gray to gray dolomite, -

broken, siliceous.

43.8 51.4 7.6 21 88-2 88-2 Light gray to yellow dolomite, .15

broken, minor red chert.

Sludge = 0.02 percent Hg.

51.4 58.0 6.6 12 89-2 - Light gray to yellow dolo- .02

mite. Sludge = 0.03 percent

Hg.

58.0 64.4 6.4 16 90-2 - Light gray to yellow dolomite, .01

minor red chert, brittle.

64.4 71.4 7.0 14 91-2 - Light gray to yellow dolomite, .19

slightly vuggy. Sludge = 0.03

percent Hg.

71.4 78.0 6.6 45 92-2 - Light gray to yellow dolomite, .01

occasional darker gray bands,

slightly vuggy.

78.0 84.4 6.4 11 93-2 - Light gray to yellow dolomite.. .04

84.4 86.3 1.9 93 94-2 - Light gray to yellow dolomite, .03

siliceous.

86.3 87.3 1.0 93 95-2 - Light gray to yellow dolomite, .23

slightly soft and few vugs,

few blebs cinnabar.

87.3 88.2 .9 93 96-2 - Light gray to yellow dolomite, .03

very few blebs cinnabar,

siliceous.

88.2 91.4 3.2 93 97-2 - Light gray to yellow dolomite, .01

slightly darker gray dolomite.

91.4 98.4 7.0 54 98-2 - Gray to light gray dolomite, .01

siliceous, minor yellow

limonite.

98.4 105.4 7.0 94 99-2 - Gray to light gray dolomite, .01

siliceous, minor yellow limonite, broken.
83

Diamond-drill hole 14--Continued

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

percent

105.4 110.4 5.0 90 100-2 100-2 Gray dolomite, calcite <0.01

stringers, siliceous,

minor yellow limonite

coating on fractures.

110.4 115.8 5.4 37 101-2 _ Same as 105.4 to 110.4 .07

feet, small blebs and

stringers cinnabar,

mostly from 112.0 to

113.0 feet.

115.8 116.2 .4 100 102-2 _ Gray dolomite, broken... .01

116.2 117.8 1.6 19 103-2 - Gray dolomite, broken. .01

Sludge = 0.04 percent

Hg.

117.8 118.4 .6 0 - - No core. Sludge = 0.02 -

percent Hg.

118.4 122.4 4.0 50 104-2 - Light gray to gray dolo- <.01

mite, siliceous, vuggy.

122.4 126.8 4.4 96 105-2 - Light gray to gray dolo- <.01

mite, siliceous.

126.8 133.4 6.6 84 106-2 - Light gray to gray dolo- <.01

107-2 - mite, siliceous, cinna- <.01

bar paint from 131.7 to

132.3 feet (107-2).

Sludge = 0.12 percent

Hg.

133.4 140.4 7.0 82 108-2 - Light gray to gray dolo- <.01

mite, siliceous, calcite lenses, broken,

vuggy from 139.4 to

140.4 feet. Sludge =

0.07 percent Hg.

140.4 142.0 1.6 75 109-2 109-2 Gray dolomite, formation -

starting to change,

softer than previously.

142.0 147.4 5.4 43 110-2 110-2 110-2 light gray to yel- <.01

llA-2 1lOA-2 low hydrothermal rock

with dark gray dolomite

inclusions (l1OA-2),

calcite, soft.

147.4 154.4 7.0 3 - 111-2 Light yellow dolomite _

with black shale inclusions, calcite.
84

Diamond-drill hole 14--Continued

Length, Core Sam le Percent

From To feet recovery, C P Description mercury

percent

154.4 163.4 9.0 26 - 112-2 Black shale, fine-grained, <0.01

broken, few small scattered

pyrite crystals, bedding

750 to 800 to long axis or

almost normal to long axis,

in places bedding has been

crushed as have pyrite

crystals.

163.4 170.4 7.0 100 113-2 - Same as 154.4 to 163.4 feet, <.01

but less pyrite.

170.4 177.3 6.9 10 114-2 - Same as 163.4 to 170.4 feet, <.01

slaty, breaks easily.

Sludge = 0.02 percent Hg.

177.3 184.4 7.1 100 115-2 - Same as 163.4 to 170.4 feet. <.01

184.4 189.0 4.6 87 116-2 - ...... .. .do. .... * ....... <.01

189.0 193.6 4.6 87 117-2 117-2 Light gray to gray dolomite, <.01

siliceous, minor calcite,

few small shale inclusions.

193.6 200.4 6.8 56 118-2 - .... .,do...., ,. .... <.01

200.4 206.6 6.2 76 119-2 - Light gray dolomite, fine- <.01

grained.

206.6 214.4 7.8 86 120-2 - Light gray dolomite, very <.01

siliceous, few dark gray

bands dolomite, at 600 to

long axis of core.

214.4 224.8 10.4 30 121-2 - . ........ ... do ............. <.01

224.8 226.4 1.6 100 122-2 - Dark gray to black dolomite, <.01

fine-grained, very hard,

siliceous, more calcite,

broken.

226.4 232.5 6.1 26 123-2.123-2 ........ ....do............. <.01
85

APPENDIX D.--ASSAYS AND DRILLING DATA ON DIAMOND-DRILL HOLES

Hole 1

Distance Core Weight, Analyses, percent

Footage drilled, obtained, grams Recovaerv percent Core, Sludge

From To feet feet Core Sludge Core Sludge Water mer- Mer- Anti- Arse-

____ ___ uycur y mony nic

0.0 5.0 5.0 5.0 3750 _ 100 - 100 0.01 - - -

5.0 8.0 3.0 1.8 1335 2043 60 60 60 .01 0.01 <0.01 0.02

8.0 13.0 5.0 3.2 2400 2502.6 64 45 60 .01 .01 <.01 .01

13.0 15.8 2.8 2.4 892 1678.4 86 85 100 .01 .01 <.01 .02

15.8 20.5 4.7 1.9 684 1612.6 40 40 60 .01 .005 <.01 .01

20.5 29.5 9.0 3.9 1410 4019.6 43 49 60 .01 .01 <.01 .02

29.5 39.4 9.9 7.9 2908 3596.8 80 50 60 .01 <.005 <.01 .02

39.4 49.6 10.2 7.7 2734 4621.2 75 70 100 .01 .01 <.01 .04

49.6 55.5 5.9 1.7 678 5234.8 29 90 100 .01 .02 <.01 .08

55.5 58.2 2.7 .5 186 2232.8 19 85 100 .22 .06 .01 .04

58.2 68.2 10.0 3.0 1291 4296.8 30 40 50 .08 .08 .01 .06

68.2 75.2 7.0 5.2 1590 1477.4 74 34 50 .06 .08 <.01 .02

75.2 85.2 10.0 8.4 4265 1563.6 84 13 50 .01 .03 - -

85.2 95.2 10.0 9.5 5160 1050.4 95 10 50 .03 .06 - -

95.2 105.2 10.0 9.4 4470 1150.4 94 13 50 .01 .04 - -

105.2 115.2 10.0 8.7 4060 1519.2 87 17 50 .03 .04 - -

115.2 125.2 10.0 9.6 4850 1430.8 96 15 50 .04 .04 - -

125.2 129.3 4.1 3.4 1970 511 83 11 50 .01 .04 - -

129.3 139.3 10.0 1.6 723 2487 16 21 50 .01 .02 - -

139.3 149.3 10.0 1.8 971 2870 18 20 50 <.005 .01 _ _

Hole 2

Distance Core Weight, Ana lyses, percent

Foot ge drilled, obtained, grams Recovery percent Core, Sludge

From To feet feet Core Sludge Core Sludge Water mer- Mer- Anti- Arsel____ ____ cury cury mony nic

0.0 7.0 7.0 1.7 1700 - 24 - 100 - - - -

7.0 11.5 4.5 4.5 4510 1990 100 39 50 <0.01 <0.005 <0.01 0.01

11.5 16.5 5.0 5.0 5050 1900 100 33 50 <.01 <.005 <.01 .01

16.5 20.5 4.0 3.0 1520 1130 75 28 50 <.01 <.005 <.01 .01

20.5 30.5 10.0 9.5 4800 2020 95 22 50 <.01 .005 <.01 .01

30.5 40.5 10.0 10.0 4700 2780 100 31 50 .03 .15 .02 .01

40.5 49.3 8.8 7.0 3740 3249 80 35 50 .21 .25 .08 .01

49.3 59.3 10.0 9.1 4635 3309 91 35 50 .25 .26 .08 .01

59.3 68.3 9.0 4.5 2380 4584 50 42 50 .02 .09 .03 .02

68.3 69.3 1.0 .4 180 509 40 47 50 .01 .09 .03 .02

69.3 70.0 .7 .0 0 650 0 71 50 .01 .08 .01 .01

70.0 76.7 6.7 .4 180 6193 6 77 100 .01 .08 .01 .01

76.7 80.0 3.3 .3 135 2865 9 71 100 <.01 .05 <.01 .01

80.0 89.1 9.1 3.2 1151 8652 35 109 100 .05 .13 <.01 .02

89.1 99.3 10.2 7.9 3890 2103 77 21 50 .01 .02 - -

99.3 109.4 10.1 3.3 1282 1819 33 19 50 <.01 .02 - -

109.4 120.0 10.6 6.3 2880 2287 60 22 50 .005 .01 - -

120.0 130.0 10.0 2.6 1109 1793 26 16 50 .005 .02 - -

130.0 140.0 10.0 1.5 850 1966 15 13 50 <.005 .02 - -
86

Hole 3

Distance Core Weight, Analyses,

Footage drilled, obtained, grams Recovery, percent percent

From To feet feet Core Sludge Core Sludge Water Core, Sludge,

mercury mercury

0.0 5.0 5.0 0.0 - - - - - - -

5.0 8.2 3.2 3.2 1760 1651 100 83 100 - <0.005

8.2 18.2 10.0 9.6 5630 1774 96 16 50 - <.005

18.2 28.2 10.0 4.6 2555 472 46 4 50 - .005

28.2 38.2 10.0 10.0 5560 1976 100 22 50 - .005

38.2 48.4 10.2 8.6 4650 1948 84 16 50 - <.005

48.4 58.0 9.6 3.2 1700 564 33 4 50 - <.005

58.0 67.8 9.8 9.8 5740 1265 100 12 50 - <.005

67.8 78.0 10.2 10.0 5350 710 98 7 50 - .01

78.0 88.0 10.0 4.0 2180 1559 40 12 50 - <.005

88.0 92.5 4.5 1.1 588 482 24 8 50 - .005

92.5 103.0 10.5 .5 264 1131 5 8 50 - .005

103.0 113.0 10.0 .3 176 1254 3 8 50 - .005

113.0 116.0 3.0 .2 112 939 6 5 50 - <.005

116.0 126.0 10.0 .0 0 1008 0 10 50 - <.005

126.0 136.0 10.0 1.0 567 1943 10 13 50 - <.005

136.0 143.0 7.0 2.2 1110 1229 31 14 50 - <.005

Hole 4

Distance Core Weight, Analyses,

Footage drilled, obtained, grams Recovery, percent percent

From To feet feet Core Sludge Core Sludge Water Core, Sludge,

I_______ ___ mercury mercury

0.0 10.0 10.0 0.0 - - - - 100 - -

10.0 14.5 4.5 1.8 1316 741 40 13 50 0.06 0.03

14.5 19.5 5.0 5.0 4560 1179 100 15 50 .03 .06

19.5 29.5 10.0 5.3 3060 987 53 8 50 .07 .04

29.5 39.9 10.4 10.1 5130 1655 97 17 50 .03 .05

39.9 50.0 10.1 5.0 2862 1787 50 14 50 .01 .02

50.0 60.0 10.0 3.8 1600 2428 38 24 50 <.01 .01

60.0 69.7 9.7 2.7 1125 2312 38 32 50 .005 <.005

69.7 80.0 10.3 6.2 2469 2400 60 27 50 .01 .01

80.0 90.6 10.6 4.5 1740 949 42 9 50 - .01

90.6 93.0 2.4 2.4 1167 0 100 0 None <.005 -

93.0 103.0 10.0 4.0 1453 0 40 0 None .01 -

103.0 110.5 7.5 1.8 547 0 24 0 None .11 -

110.5 120.5 10.0 9.4 5160 0 94 0 None .01 -

120.5 130.5 10.0 9.2 5040 0 92 0 None .01 -

130.5 140.5 10.0 .9 442 0 9 0 None .01 -

140.5 150.2 9.7 1.7 726 0 18 0 None .01 -
87

Hole 5

Distance Core Weight, Analyses,

Footage drilled, obtained, grams Recovery, percent percent

From To feet feet Core Sludge Core Sludge Water Core, Sludge,

I__ _ _ _ ____mercury _ __ _ I_____ mercury

0.0 2.5 2.5 1.1 627 - 44 - 60 0.06 -

2.5 12.5 10.0 .2 85 2640 2 23 50 .01 0.04

12.5 15.0 2.5 .2 72 839 8 35 50 .02 .03

15.0 16.5 1.5 1.0 419 146 75 13 50 .02 .03

16.5 19.5 3.0 3.0 1287 786 100 40 50 <.005 .01

19.5 23.5 4.0 .3 122 6791 8 165 100 <.005 .03

23.5 27.5 4.0 .5 220 4991 12 165 100 .03 .03

27.5 31.9 4.4 .5 223 1525 10 41 50 .005 .04

31.9 40.0 8.1 5.0 2123 3436 62 46 50 .20 .02

Hole 6

Distance Core Weight, Analyses,

Foot ge drilled, obtained, grams Recovery. p rcent percent

From To feet feet Core Sludge Core Sludge Water Core, Sludge,

I____ _mercury-mercury

0.0 5.0 5.0 0.0 - 1326 - 16 30 - 0.48

5.0 10.0 5.0 .0 - 18864 - 225 100 - .69

10.0 13.0 3.0 .0 - 7748 - 157 100 - .56

13.0 14.5 1.5 1.1 801 1815 73 118 100 0.20 12.26

14.5 19.8 5.3 2.5 1572 2365 47 43 50 .10 .12

19.8 22.8 3.0 1.1 765 4232 37 116 100 .57 .21

22.8 25.5 2.7 .6 217 1456 22 77 100 .12 .14

25.5 27.0 1.5 .6 315 3174 40 233 100 .23 .17

27.0 31.5 4.5 4.2 2150 4751 93 171 100 .04 .12

Hole 7

Distance Core Weight, Analyses,

Foota ge drilled, obtained, grams Recovery, percent percent

From To feet feet Core Sludge Core Sludge Water Core, Sludge,

_I_ _ _mercury mercury

0.0 5.0 5.0 0.0 - 2348 - 46 50 - 3.04

5.0 8.5 3.5 .0 - 1735 - 48 50 - 4.32

8.5 12.0 3.5 .2 94 8931 6 458 100 - 5.13

12.0 13.5 1.5 .5 243 6193 33 468 100 3.38 1.60

13.5 16.0 2.5 .3 77 5786 12 450 100 - 6.53

16.0 17.5 1.5 .3 - 5324 20 380 100 - 3.55

17.5 21.5 4.0 .2 - 18443 5 440 100 - 10.98

21.5 24.0 2.5 .0 - 7928 - 310 100 - 2.69

24.0 25.0 1.0 .0 - 2214 - 260 100 - .56
88

Hole 8

Distance Core Weight, Analyses,

Foota ge drilled, obtained, 9rams Recovery, Parcent percent

From To feet feet Corore Sludge re Sludge Water Core, Sludge,

_________ ______ mercury mercury

0.0 7.0 7.0 0.0 - - - - 50 - -

7.0 13.0 6.0 6.0 5663 1107 100 11 50 0.03 0.62

13.0 15.5 2.5 2.0 1823 1622 80 36 50 <.005 .06

15.5 19.5 4.0 4.0 4700 805 100 10 50 .01 .11

19.5 24.5 5.0 5.0 2606 2226 100 48 50 <.005 .07

24.5 29.5 5.0 4.7 2502 2346 94 48 50 .05 .07

29.5 34.5 5.0 4.9 2459 1566 98 35 50 .35 .11

34.5 37.7 3.2 2.0 838 2723 63 95 100 .01 .04

37.7 42.5 4.8 4.8 2315 2685 100 65 100 .01 .13

42.5 47.5 5.0 5.0 2225 2443 100 62 100 <.005 .02

47.5 54.5 7.0 5.0 2140 2706 71 44 60 <.005 .03

54.5 59.5 5.0 4.5 2078 1915 90 44 60 .005 .03

59.5 64.5 5.0 4.9 3030 1956 98 35 60 .005 .04

64.5 66.0 1.5 1.4 605 658 93 55 60 .005 .03

66.0 70.5 4.5 4.5 2475 1603 100 37 60 .01 .03

70.5 74.0 3.5 3.5 2100 1217 100 33 50 .005 .02

74.0 79.0 5.0 5.0 3050 987 100 18 50 .005 .01

79.0 83.5 4.5 3.3 1660 1885 73 41 50 .005 .03

83.5 89.3 5.8 4.9 2530 2104 85 20 50 .005 .04

89.3 93.5 4.2 4.2 1865 1258 100 38 50 .12 .04

93.5 98.5 5.0 4.5 2002 0 90 - - .24 -

98.5 100.0 1.5 1.2 409 1874 80 186 100 .04 .04

100.0 103.3 3.3 1.1 418 5225 33 169 100 .02 .05

103.3 104.0 .7 .4 108 3249 57 775 100 .13 .05

104.0 108.0 4.0 3.0 1276 1809 75 53 70 .02 .04

108.0 117.0 9.0 2.5 1176 9445 28 90 100 .02 .04

117.0 128.0 11.0 9.3 3418 4370 85 57 60 .34 .18

128.0 138.0 10.0 4.6 1584 2973 46 37 60 .01 .10

138.0 148.0 10.0 2.0 870 1482 20 13 60 .01 .06

148.0 157.9 9.9 4.1 1765 3398 41 33 60 <.005 .08

157.9 167.8 9.9 4.6 1970 3782 41 33 60 .005 .09

167.8 177.9 10.1 10.1 4540 4480 100 56 60 <.005 .11

177.9 185.0 7.1 5.0 2101 2316 71 38 60 .005 .08

185.0 192.0 7.0 5.0 2282 4587 63 58 60 .005 .09

192.0 203.7 11.7 10.7 5165 3611 90 34 60 .005 .09
89

Hole 9

Foot Re Distance Core Weight, Recovery, percent Analyses percent

From To drilled, obtained, grams Core Sludge Water Core, Sludge,

feet feet Core Sludge mercury mercury

0.0 7.4 7.4 1.2 - - - - 100 - _

7.4 8.8 1.4 1.1 739 - 79 - 100 <0.01 _

8.8 9.9 1.1 1.0 803 - 91 - 100 .01 -

9.9 13.0 3.1 1.1 605 452 35 11 50 .01 0.06

13.0 15.0 2.0 1.5 661 690 75 39 50 .01 .01

15.0 19.2 4.2 1.2 574 1454 29 30 50 <.01 .25

19.2 23.2 4.0 3.7 1897 750 93 20 50 .01 .02

23.2 28.5 5.3 2.0 787 908 40 19 50 .01 .01

28.5 35.6 7.1 3.5 1647 955 50 13 50 <.01 .07

35.6 38.8 3.2 3.2 1642 567 100 19 50 .42 .02

38.8 43.2 4.4 3.2 1637 502 73 11 50 .01 .01

43.2 50.6 7.4 1.1 480 5367 15 64 80 .01 .01

50.6 55.6 5.0 4.8 2422 2363 91 48 50 <.01 .02

55.6 58.2 2.6 2.1 928 472 81 21 50 <.01 .01

58.2 65.5 7.3 3.6 1685 2950 49 37 50 <.01 .02

65.5 70.5 5.0 5.0 2430 1542 100 36 50 <.01 .03

70.5 75.5 5.0 4.4 2150 2669 88 58 60 <.01 .01

75.5 80.5 5.0 2.5 1198 2260 50 43 60 <.01 .01

80.5 82.5 2.0 .8 518 2981 40 92 100 <.01 .02

82.5 90.5 8.0 .8 356 2280 10 24 60 .01 .02

90.5 95.5 5.0 .9 360 2648 18 51 60 <.01 .01

95.5 100.5 5.0 1.0 505 3501 20 54 60 <.01 .02

100.5 105.5 5.0 .7 362 2267 14 33 60 <.01 .02

105.5 110.5 5.0 .0 _ 2106 _ _ _ _ .02

Hole 10

Foota e Distance Core Weight, Recovery, percent Analyses, percent

From To drilled, obtained, grams Core Sludge Water Core, Sludge,

feet feet Core Sludge mercury mercury

0.0 10.0 10.0 0.0 - - - - 100 - -

10.0 15.4 5.4 .8 317 2455 15 44 60 <0.01 <0.01

15.4 20.2 4.8 1.3 491 2187 27 48 60 <.01 .01

20.2 25.4 5.2 2.8 1070 1462 54 33 60 .01 .01

25.4 30.4 5.0 1.7 799 2107 34 38 60 <.01 .01

30.4 35.4 5.0 1.7 795 1727 34 30 60 <.01 <.01

35.4 40.9 5.5 1.6 788 1525 29 23 60 <.01 .01

40.9 43.4 2.5 1.6 653 1265 64 58 60 <.01 .01

43.4 45.4 2.0 1.2 542 771 60 39 60 <.01 .03

45.4 50.5 5.1 3.8 1796 1963 75 40 60 <.01 .01

50.5 55.5 5.0 3.9 2010 2760 78 49 60 <.01 .01

55.5 58.8 3.3 2.6 1130 871 79 31 50 <.01 .01

58.8 65.8 7.0 6.4 3292 2363 92 36 50 <.01 .01

65.8 70.8 5.0 4.7 2282 1304 94 29 50 .01 <.01

70.8 75.8 5.0 4.7 2290 1057 94 24 50 <.01 <.01

75.8 80.2 4.4 2.5 1212 2224 57 47 50 <.01 <.01

80.2 85.2 5.0 2.7 1360 2042 54 36 50 <.01 .01

85.2 90.2 5.0 2.8 1417 2142 57 37 50 <.01 .01

90.2 91.5 1.3 1.3 744 3879 100 291 100 <.01 <.01

91.5 102.3 10.8 .7 264 3498 7 34 50 <.01 <.01

102.3 110.9 8.6 2.8 1237 3492 33 38 50 <.01 <.01

110.9 116.3 5.4 2.9 1358 2947 54 52 50 <.01 <.01

116.3 121.0 4.7 2.5 1062 2050 53 45 50 <.01 <.01
90

Hole 11

Distance Core Weight, Analyses,

Foota ge drilled, obtained, grams Recovery, percent percent

From To feet feet Core Sludge Core Sludge Water Core, Sludge,

mercury mercury

0.0 7.0 7.0 0.0 - - - - 50 - -

7.0 12.5 5.5 .6 400 1150 11 12 50 <0.01 0.02

12.5 17.6 5.1 .7 380 1048 14 15 50 <.01 .02 f

17.6 24.8 7.2 3.0 1182 1932 42 29 50 <.01 <.01

24.8 29.8 5.0 2.3 936 2549 46 54 50 <.01 .01

29.8 31.8 2.0 .7 351 747 35 31 50 <.01 <.01 s

31.8 33.8 2.0 .3 117 881 15 43 50 <.01 <.01

Hole 12

Distance Core Weight, Analyses,

_Footage drilled, obtained, grams Recovery, percent percent

From To feet feet Core Sludge Core Sludge Water Core, Sludge,

I__ _ _ __ __ _ __ _ __ _mercury _ __ ___ mercury

0.0 7.0 7.0 0.0 _- - - 50 - -

7.0 15.8 8.8 .7 329 1759 8 16 50 <0.01 <0.01

15.8 20.0 4.2 1.3 581 2909 31 63 60 <.01 <.01

20.0 25.8 5.8 3.3 1648 2446 57 62 60 <.01 <.01

25.8 35.5 9.7 6.7 2857 4085 69 47 60 <.01 <.01

35.5 45.5 10.0 6.7 2885 1620 67 18 50 <.01 .02

45.5 55.5 10.0 3.4 1621 5038 34 43 50 <.01 .05

55.5 60.0 4.5 1.6 745 1750 36 35 50 <.01 .02

60.0 66.8 6.8 .0 - 5565 - 70 100 <.01 .02

66.8 72.0 5.2 .0 - 5729 - 92 100 <.01 <.01

72.0 78.8 6.8 1.1 665 4543 16 42 60 <.01 <.01

78.8 85.0 6.2 1.2 446 3955 19 65 60 <.01 <.01

85.0 95.8 10.8 3.0 1298 4405 28 39 50 <.01 <.01

95.8 105.8 10.0 .4 191 4523 4 35 50 <.01 <.01

105.8 112.8 7.0 2.2 979 1925 32 26 50 <.01 <.01

Hole 13

Distance Core Weight, Analyses,

Foota ge drilled, obtained, grams Recov~erv percent percent

From To feet feet Core Sludge Core Sludge Water Core, Sludge,

I___ __mercury _ __ __ _ __ __ __ _ __ mercury

0.0 6.0 6.0 0.0 - _ _ _ 50 - _

6.0 10.0 4.0 3.0 2591 - 75 - - <0.01 -

10.0 15.0 5.0 2.2 973 1300 44 35 50 .01 0.01

15.0 20.3 5.3 3.5 1550 3573 66 108 100 .01 .03

20.3 25.3 5.0 .7 287 2944 14 77 80 .01 .03

25.3 30.0 4.7 1.2 529 287 26 8 20 <.01 .14

30.0 35.0 5.0 2.4 967 - 48 - - <.01 -
91

Hole 14

Distance Core Weight, Analyses,

Foot age drilled, obtained, grams Recoverypercent percent

From To feet feet Core Sludge Core Sludge Water Core, Sludge,

mercury mercury

0.0 6.0 6.0 0.0 - - - - 100 -

6.0 10.5 4.5 4.5 4619 - 100 - 100 0.10 _

10.5 15.0 4.5 .5 281 - 11 - 100 .10 -

15.0 20.6 5.6 .5 204 2351 9 39 40 .14 0.17

20.6 25.6 5.0 3.7 1622 282 74 8 40 .03 .11

25.6 31.4 5.8 1.2 503 1025 21 17 40 .01 .02

31.4 38.4 7.0 3.0 1268 684 60 18 40 .01 .03

38.4 43.8 5.4 .1 45 1944 5 30 40 .01 .01

43.8 51.4 7.6 1.6 696 1795 21 20 40 .15 .02

51.4 58.0 6.6 .8 333 2772 12 38 40 .02 .03

58.0 64.4 6.4 1.0 379 1726 16 28 40 .01 .02

64.4 71.4 7.0 1.0 441 2041 14 25 40 .19 .03

71.4 78.0 6.6 3.0 1457 1254 45 17 40 .01 .02

78.0 84.4 6.4 .7 357 2015 11 24 40 .04 .04

84.4 91.4 7.0 6.5 1018 621 93 31 40 .09 .05

91.4 98.4 7.0 3.8 1921 1786 54 22 40 .01 .03

98.4 105.4 7.0 3.3 1611 1012 47 13 40 .01 .03

105.4 110.4 5.0 4.5 2163 927 90 21 40 <.01 .03

110.4 115.8 5.4 2.0 1158 1816 37 24 40 .07 .02

115.8 116.2 .4 .4 197 - 100 - - <.01 -

116.2 117.8 1.6 .3 177 372 19 15 40 <.01 .04

117.8 118.4 .6 .0 - 1174 - 120 100 <.01 .02

118.4 122.4 4.0 2.0 992 954 50 21 40 <.01 .08

122.4 126.8 4.4 4.2 2429 605 96 14 10 <.01 .12

126.8 133.4 6.6 5.2 2203 510 84 10 10 <.01 .07

133.4 140.4 7.0 5.7 3065 198 82 3 10 <.01 .04

140.4 147.4 7.0 3.0 1408 - 43 - 10 <.01 -

147.4 154.4 7.0 .2 79 - 3 - 10 <.01 -

154.4 157.0 2.6 .0 - 101 - 3 20 <.01 .02

157.0 163.4 6.4 2.3 1012 772 36 11 30 <.01 .02

163.4 170.4 7.0 7.0 3339 444 100 7 20 <.01 .02

170.4 177.3 6.9 .7 312 681 10 8 20 <.01 .02

177.3 184.4 7.1 7.1 3639 - 100 - 10 <.01 .02

184.4 193.6 9.2 8.0 2350 324 87 6 10 <.01 <.01

193.6 200.4 6.8 3.8 1514 513 56 9 10 <.01 .01

200.4 206.6 6.2 4.7 2267 183 76 3 5 <.01 .01

206.6 214.4 7.8 6.7 3825 15 86 - 5 <.01 -

214.4 226.4 12.0 4.6 618 - 38 - - <.01 _

226.4 232.5 6.1 1.6 816 - 26 - - <,01 _
92

APPENDIX E.--PETROGRAPHIC ANALYSES OF DIAMOND-DRILL CORES

The same numbering system is used here as in appendix C. The following

legend applies to all petrographic samples in appendix E:

P--Predominant ................ Over 50 percent.

A--Abundant .................. 10 - 50 percent.

S--Subordinate ................. 2 - 10 percent.

M--Minor ...................... 0.5 - 2 percent.

F--Few ........... .......... 0.1 - 0.5 percent.

T--Trace ................ Less than 0.1 percent.

C--Rock classification.

Samp le

3-2 7-2 11-2 15-2 18-2 21-2 22-2 24-2 32-2 38-2 40-2 42-2

Diamond-drill hole.. 9 9 9 9 9 9 9 9 10 10 10 10

Rock classification:

Altered volcanic.. - - - - - - - - - - - C

Dolomite .......... - - C C - - - - - - C _

Hydrothermal rock. - - - - - - C - - - - _

Limestone .... to..O. C - - - - C - C - - -_

Phyllite.......... - - - - - - C - -

Shale ............. - C - - C - _ - C -_

Vein calcite ... _ C C _ _ - C -

Mineral:

Ankerite.......... __ _ . _ _ _ 

Biotite ........... - - - - - - - - A

Calcite ........... P _ . S A P S P - _ - F

Carbon ............ - - - - _ - - S _ -_ _ 

Chlorite ..... .. - A - - P _ A A _ P _ -

Cinnabar ......... . .- - S -_ _ _ _ _ _ _ -

Dolomite .......... - - P P T - - S _ - P S

Illite ....- _ A A -... A A A P A - A

Kaolin ...... _ _ ... - - S - _ S

Limonite ...n e. - M F - S S M -_ M

Manganese dioxide. - _ _ _ S - _ _ _ _ _

Pyrite ..... _..- _ T -_ _ _ - - F

Quartz.S ... A M _ _ F _ - - M

Sanidine .......... _ _ _ 

Zeolite ....... _._... _ _ _ _
93

Sample

43-2 44-2 45-2 46-2 47-2 47A-2 48-2 50-2 51-2 52-2 57-2

Diamond-drill hole ......... 10 10 10 10 10 10 10 10 10 10 11

Rock classification:

Altered volcanic ......... C C C C - - C C - - -

Dolomite ................. _ _ _ _ _ - - - C

Hydrothermal rock ........ - - - - C -

Limestone ............... . - - - - - - _ - C C -

Phyllite ................. _ _ _ _ _ _ 

Shale .................... - - - - - C

Vein calcite ............. _ _ _ _ _ _ 

Mineral:

Ankerite ................. - - - S A -_ _ _ _ _ 

Biotite . ................. - A S M - - A A _ _ _ 

Calcite . .......... N. S S - - - S A P P A

Carbon . .................. M M

Chlorite . ................ P A M A

Cinnabar . ................ _

Dolomite ................. - F A F A _ A

Illite . .......... A A A A A A A A _ -_ 

Kaolin .... ............... A

Limonite . ......... A A A S S A M - T - F

Manganese dioxide ........ _ _ _ 

Pyrite . .................. - - - T S T - T

Quartz ..... . - S - A A M _ - A _ _ 

Sanidine . ................ - F

Zeolite . .......

Sa mple

57A-2 58-2 64-2 68-2 70-2 72-2 73-2 76-2 80-2 85-2 88-2

Diamond-drill hole ......... 11 11 12 12 12 12 12 13 13 14 14

Rock classification:

Altered volcanic ......... _ _ _ _ _ _ _ _ _ _ _ 

Dolomite ................. - - - C C - - C C C C

Hydrothermal rock ........ - - - - - C -

Limestone ............... . C - - - -_ _ _ _ _ _ 

Phyllite ................ _. _ _ _ _ 

Shale ............... ..... - C C - - - C _ -_ _ 

Vein calcite ............. - - - - - - C _ _ _ _ 

Mineral:

Ankerite ................. _ _ _ _ _ _ _ 

Biotite ................. _. _ _ _ _ _ _ 

Calcite .................. P S - S S - A A S S M

Carbon ................... _ _ _ _ _ _ _ 

Chlorite ................. - - A - - S -_ _ _ _ 

Cinnabar ................. - - - - - F

Dolomite ................. - - - P P S _ P P P P

Illite ................... _ P P _ M A _ -_ _ 

Kaolin ................... _

Limonite .............. *.. T M M M M S _ F _ _ _ 

Manganese dioxide ........ _ _ _ _ _ 

Pyrite ................... - - - - - S S _ _ _ _ 

Quartz ...... . . ..... . - - - - A P -_ _ - S

Sanidine ................. _ _ _ _ 

Zeolite .. .. - I A A I - _ _ _ -
94

Sample

98-2 100-2 109-2 110-2 1lOA-2 111-2 112-2 117-2 123-2

Diamond-drill hole ..... 14 14 14 14 14 14 14 14 14

Rock classification:

Altered volcanic ..... - - - - - - - - -

Dolomite ........... . .C C C _ C C _ C C

Hydrothermal rock .... _ _ _ C _ _ _ _ _ 

Limestone. .......... _ _ _ _ _ _ 

Phyllite .................._________

Shale. ................... C__

Vein calcite ......... _ C _ C _ _ C

Mineral:

Ankerite __ .......... _ _ __- ..... 

Biotite ....... ............

Calcite.............. T P S A T S _ F S

Carbon ...... . ........ . - - _ F _ T T

Chlorite ........... .. - - _ S _ _ _ _ _ 

Cinnabar...... ....... - T _ _ _ _ _ _ _ 

Dolomite ............. P A P _ P P _ P P

Illite, ...... o........ _ __ P__

Kaolin ..................

Limonite......0..T .. T __ T S _

Manganese dioxide.... _ _ - _ _ _ _ _ _ 

Pyrite ........ ..... .O..______ M__

Quartz..o.... .0.0....... _ _ _ A _ S S A -

Sanidine ....... . . . . . _ ._ . .I..... _ _ _ _ _0492

Zeolite ............... _o **~ I

INT.-BU.OF MINES,PGH.,PA. 10492