U.S. Geological Survey Open-File Report 99-xxx - Alaska Resource

2423 Pages·2016·4.66 MB·English

Alaska Resource Data File, New and
Revised Records Version 1.7

By U.S. Geological Survey

Open-File Report 2008-1225

2008

Any use of trade, firm, or product names is for descriptive purposes only and does not imply
endorsement by the U.S. Government.

U.S. DEPARTMENT OF THE INTERIOR
U.S. GEOLOGICAL SURVEY
Alaska Resource Data File AN002
Site name(s): Lucky Shot; Willow Creek Mines Inc.
Site type: Mine
ARDF no.: AN002
Latitude: 61.779 Quadrangle:AND-7
Longitude:149.4078
Location description and accuracy:
The portal of the Lucky Shot Mine is on the northwest valley wall of Craigie Creek, 1.8 miles northeast of
the junction of Craigie Creek and Willow Creek. The mine is marked by a symbol labeled 'Lucky Shot
Mine' on the Anchorage D-7 1:63,360-scale topographic map. It is near the center of section 35, T. 20 N., R.
1 W. of the Seward Meridian. The underground workings and exploration activities extend far beyond the
the portal. The adjacent War Baby Mine (AN003) and the Lucky Shot Mine were long ago consolidated into
a single property which now is commonly referred to as the Lucky Shot.
Commodities:
Main: Au
Other: As, Cu, Pb, Sb, Te, Zn
Ore minerals: Arsenopyrite, chalcopyrite, galena, gold, pyrite, sphalerite, stibnite, tellurides, tetrahedrite
Gangue minerals: Quartz
Geologic description:
The Lucky Shot Mine consists of 4 blocks - the Coleman, Lucky Shot, War Baby, and Murphy blocks. In
the early days of the district, these were more or less contiguous if somewhat separate properties at least in
name but they are being explored and developed as a single property (Full Metal Minerals, 2010a; Stevens,
2010). The deposit consists of quartz veins along shear zones that cut the Late Cretaceous Willow Creek
Pluton, which is jointed and sheeted near the surface but less so underground. The pluton is zoned; the outer
part consists of hornblende quartz diorite and lesser hornblende tonalite; the core consists of hornblende-
biotite granodiorite and lesser hornblende-biotite quartz monzodiorite and biotite quartz monzonite.
The classic mesothermal quartz veins at the Lucky Shot occur along shear zones that exhibit both ductile
and brittle properties; the shear zones are up to 100 feet wide. The veins are between two major
northeastward-dipping transverse faults. The quartz veins that were mined prior to WWII were generally 2
to 4 feet wide; they strike about N 80 E, and dip about 40 N. Post mineral faults offset the veins up to 800
feet and the quartz in the veins often is fractured. There are two generations of quartz veins. An older group
is generally parallel to southwest-dipping joints in the pluton. These veins contain three different suites of
ore minerals: 1) chalcopyrite, pyrite, and arsenopyrite; 2) pyrite and stibnite; and 3) sparse pyrite, sphalerite,
and minor gold. The younger and economically important veins occur along the major shear zones. Pyrite is
the most common ore mineral in them; arsenopyrite and galena are often present; scheelite is locally
present; and there are trace tellurides including nagyagite, altaite, and possibly coloradoite. The wall rocks
are intensely altered near the veins. Adjacent to the veins, the wall rock is bleached white or gray-green with
much sericite, clay, and carbonates. There is an outer zone of propylitic alteration. There are two periods of
mineralization, 66 Ma and 55 to 57 Ma (Madden-McGuire and others, 1988; Harlan, 2003). Fluid inclusion
studies and isotope geochemistry indicate that the temperature of the ore forming fluids was 300 to 325
degrees (Burleigh, 1987, Silberman and others, 1978).
During the mining before WWII, the stopes along the vein averaged about 5 feet thick, the grade of the ore
was typically a half ounce to two ounces per ton and the workings only went down to 500 feet or less below
the surface (Stevens, 2010). The work since 2005 has revealed that there are much wider mineralization,
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Alaska Resource Data File AN002
even if at lower grade, and that the mineralization extends well below and beyond the old workings. The
mineralization at the Lucky Shot has been traced for more than 4,000 meters horizontally, has a vertical
extent of at least a thousand meters and has an average width of about 400 meters (Stevens, 2010). Over the
last half century or more there have been several estimates of the gold resources of the Lucky Shot Mine.
Most are now of little more than historic interest in view of the recent exploration. A resource estimate on
the Coleman Zone was completed by Miranda Gold Corp. in September 2014 (Linebarger, 2014).
In March 2016, Miranda and Gold Torrent announced an updated resource estimate for the Willow Creek
project, including measured and indicated resources of 121,500 ounces of gold averaging 18.3 grams of gold
per tonne and 12,100 ounces of silver averaging 1.8 grams of silver per tonne contained in 206,600 tonnes
of material. Inferred mineral resources include 59,000 tonnes of material that contain 35,150 ounces of gold
averaging18.5 grams of gold per tonne and 2,900 ounces of silver averaging 1.5 grams of silver per tonne
(Black and others, 2016a).
Alteration:
The wall rocks are intensely altered near the veins. Adjacent to the veins, the wall rock is bleached white
or gray-green, with much sericite, clay, and carbonates. There is an outer zone of propylitic alteration
(Madden-McGuire and others, 1988; Harlan, 2003).
Age of mineralization:
Late Cretaceous or younger (66 Ma and 55 to 57 Ma); veins cut the Late Cretaceous Willow Creek Pluton
(Madden-McGuire and others, 1988; Harlan, 2003).
Generic deposit model:
Deposit model:
Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a).
Deposit model number (After Cox and Singer, 1986 or Bliss, 1992):
36a
Production Status: Yes; medium
Site Status: Active
Workings/exploration:
Gold was discovered in the Lucky Shot area in 1918 and mining began in 1922 (Stoll, 1997, is a detailed
history of the mining at the Lucky Shot and other mines in the Willow Creek district.). Mining continued
fairly regularly until 1942; the mine did not reopen after WWII. Ensearch Exploration Inc. obtained the
property in 1979 and did considerable underground work and exploration drilling. A 100-ton-a-day mill was
built and about 10,000 tons of ore was milled. Several companies continued exploration into the early 1990s
and another 1,000 tons of ore was mined. In 2005, Full Metals Minerals Corp. began intensive exploration
of the Lucky Shot (Full Metal Minerals Corp., 2010a). Through 2008, Full Metal Minerals diamond drilled
164 holes; sampled the old dumps and underground workings; rehabilitated, improved, and sampled the old
underground workings; and mined a bulk sample for metallurgical testing. In 2009, they drilled another 27
holes with several notable intercepts with 24.14 to 102.00 grams of gold per tonne (Full Metal Minerals
Corp., 2010b). In the late Fall of 2009, they finalized an option agreement with Harmony Gold Corporation
to continue exploring the property (Full Metal Minerals Corp., 2009). In November 2013, Miranda Gold
Corp. (Miranda) entered a lease agreement with Alaska Hardrock Inc. and the following year Miranda
completed a resource estimate on the Coleman Zone (Linebarger, 2014).
Production notes:
The Lucky Shot Mine and the adjacent War Baby Mine (AN003) were combined prior to WWII and both
mines were simultaneously operated by Willow Creek Mines. Stoll (1997) estimated that the total
production to 1951 from the combined mines was about 252,000 ounces of gold.
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Reserves:
A National Instrument 43-101 compliant resource estimate on the Coleman Zone was completed by
Miranda Gold Corp. in September 2014. The resource was calculated using a 7 gram per tonne gold cutoff
grade. The measured resource was calculated to be 11,500 tonnes at 28.5 grams per tonne gold, yielding
10,500 troy ounces. The indicated resource was calculated to be 67,200 tonnes at 23.9 grams per tonne gold,
yielding 51,600 troy ounces. The inferred resource was calculated to be 5,300 tonnes at 24.2 grams per
tonne gold, yielding 4,100 troy ounces (Linebarger, 2014).
In March 2016, Miranda and Gold Torrent announced an updated resource estimate for the Willow Creek
project, including measured and indicated resources of 121,500 ounces of gold averaging 18.3 grams of gold
per tonne and 12,100 ounces of silver averaging 1.8 grams of silver per tonne contained in 206,600 tonnes
of material. Inferred mineral resources include 59,000 tonnes of material that contain 35,150 ounces of gold
averaging18.5 grams of gold per tonne and 2,900 ounces of silver averaging 1.5 grams of silver per tonne
(Black and others, 2016a). All estimated resources are based on a cutoff grade of 5.0 grams of gold per
tonne, a long-term gold price of $1,265 per ounce, and assumed metallurgical recoveries of 80 percent.
Improved understanding of the geologic controls on mineralization resulted in a significant increase in the
mineral-resource estimate for the Willow Creek project. In total, mineral resources at the Willow Creek
project include eight veins in the Coleman area and two veins in the Lucky Shot area (AN002), and are
based on information from 174 drill holes. Potential exists to increase the mineral resources through drilling
down-dip extensions of the Coleman and Lucky Shot area, and the exploration targets in the War Baby (AN
003) and Murphy areas along strike to the east (Athey and Werdon, 2017). In July 2016, a newly completed
NI 43-101 preliminary feasibility study reported proven and probable mineral reserves of 93,274 ounces of
gold contained in 207,000 tonnes of material grading an average of 14.0 grams of gold per tonne (Black and
others, 2016b).
The Willow Creek project is currently being developed through a joint-venture partnership between
Miranda Gold Corp. and Gold Torrent Inc., with Gold Torrent currently earning a 70 percent equity interest
through the funding of the first $10 million in development costs (Athey and Werdon, 2017).
Additional comments:
References:
Athey, J.E. and Werdon, M.B., 2017, Alaska's mineral industry 2016: Alaska Division of Geological &
Geophysical Surveys Special Report 72. http://doi.org/10.14509/29748
Black, Z.J., Brown, J.J., and Spiller, Erik, 2016a, National Instrument 43-101 technical report: mineral
resource assessment for the Willow Creek project, Matanuska-Susitna Borough, Alaska, USA, 136 p.
http://www.goldtorrentinc.com/news/2016/4/19/miranda-gold-files-updated-technical-report-for-the-willow-
creek-project-alaska (last accessed 8/25/2017)
Black, Z.J., Brown, J.J., and Spiller, Erik, 2016b, National Instrument 43-101 technical report: preliminary
feasibility study for the Lucky Shot project, Matanuska-Susitna Borough, Alaska, USA, 265 p.
http://www.goldtorrentinc.com/news/2016/4/19/miranda-gold-files-updated-technical-report-for-the-willow-
creek-project-alaska (last accessed 8/25/2017)
Burleigh, R.E., 1987, A Stable Isotope, Fluid Inclusion and Ore Petrographic Study of the Gold Quartz
Veins in the Willow Creek Mining District. Masters Thesis, University of Alaska.
Cox, D.P. and Singer, D.A., eds., 1986, Mineral deposit models: U.S. Geological Survey Bulletin 1693, 379
p.
Full Metal Minerals Corp., 2009, Full Metal announces signing of option agreement on its Lucky Shot
property:
http://www.fullmetalminerals.com/s/NewsReleases.asp?ReportID=371329&_Type=News&_Title=Full-
Metal-Announces-Signing-of-Option-Agreement-on-its-Lucky-Shot-Property (News release dated Nov 9,
2009; as of July 13, 2015, link no longer valid).
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Alaska Resource Data File AN002
Full Metal Minerals Corp, 2010a, Lucky Shot: http://www.fullmetalminerals.com/s/luckyshot.asp (as of
February 23, 2010; as of July 13, 2015, link no longer valid).
Full Metal Minerals Corp, 2010b, Full Metal intersects 36.38 g/t Au over 7.3 meters at Lucky Shot;
underground exploration to commence:
http://www.fullmetalminerals.com/s/NewsReleases.asp?ReportID=384752&_Type=News&_Title=Full-
Metal-Intersects-36.38-gt-Au-over-7.3-Meters-at-Lucky-Shot-Underground.. (News release dated February
11, 2010; as of July 13, 2015, link no longer valid).
Harlan, S.S, Snee, L.W., Vielreicher, R.M., Goldfarb, R.G., Mortensen, J.K., and Bradley, D.C., 2003, Age
and cooling history of gold deposits and host rocks in the Willow Creek Mining Districts), in Geological
Society of America, Abstracts with Programs, vol. 35, no. 6, p. 235.
Madden-McGuire, D.J., Silberman, M.L., and Church, S.E., 1988, Geologic Relationships, K-Ar Ages, and
Isotopic Data from the Willow Creek Gold Mining District, Southern Alaska, in Abstracts of the U.S.
Geological Survey, central region; 1988 poster reviews, eds. C.E. Barker and A.B. Coury: U.S. Geological
Survey Open-File Report 88-643, 6 p.
Silberman, M.L., O’Leary, R.M., Csejtey, B. Jr., Smith, J.G., and Connor, C.L., 1978, Geochemical
anomalies and Isotopic ages in the Willow Creek mining district, southwestern Talkeetna Mountains,
Alaska: U.S. Geological Survey Open-File Report 78-233.
Stevens, D.L., 2010, Lucky Shot project, Willow Creek Mining District, south-central Alaska: Technical
Report prepared for Harmony Gold Corp., 87 p. (posted on www.sedar.com, February 2, 2010).
Stoll, W.M., 1997, Hunting for gold in Alaska's Talkeetna Mountains 1897-1951--with a background sketch
Primary Reference:Stevens, 2010
Reporter(s): D.P. Bickerstaff (USGS); S.W. Huss (USGS); D.J. Grybeck (Contractor, U.S. Geological
Survey); N.V. King (Alaska Earth Sciences); M.B. Werdon (DGGS)
Last report date: 2017-08-26
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Alaska Resource Data File AN003
Site name(s): War Baby; Willow Creek Mines Inc.
Site type: Mine
ARDF no.: AN003
Latitude: 61.7811 Quadrangle:AND-7
Longitude:149.4016
Location description and accuracy:
The War Baby Mine is marked with an adit symbol and the label 'War Baby' on the Anchorage D-7
1:63,360-scale topographic map. It is on the northwest valley wall of Craigie Creek about 5,000 ft east of
VABM Box, near the center of section 35, T. 20 N., R. 1 W. The adjacent Lucky Shot Mine (AN002) and
the War Baby mine have long been consolidated into a single property which now is referred to as the
Lucky Shot.
Commodities:
Main: Au
Other: Cu
Ore minerals: Gold
Gangue minerals: Quartz
Geologic description:
Located in 1918, The War Baby Mine quickly saw the erection of a small mill. The first production from
the mine occurred in 1919 after two short tunnels and a crosscut were driven. Willow Creek Mines took
over the property in 1921. The War Baby was mined, with interruptions, from 1919 until 1940. There were
over 2,000 ft of underground workings on 3 levels. Ray (1933) reported that production from 1922 through
1927 was from a single stope measuring 175 by 250 ft with a maximum width of 10 to 12 ft. The ore mined
through 1927 averaged 2.18 ounces of gold per ton (Ray, 1933). There may have been some copper
production. By 1950, the mine had long since closed and the workings were inaccessible (Ray, 1954).
Chapin (1920) reported that four or five parallel quartz veins at the War Baby Mine cut the Late
Cretaceous Willow Creek Pluton. The pluton is zoned: the outer part consists of hornblende quartz diorite
and lesser hornblende tonalite; the core consists of hornblende-biotite granodiorite, and lesser hornblende-
biotite quartz monzodiorite and biotite quartz monzonite. Wallrock alteration is intense within a few inches
of the veins but seldom extends more than 10 to 12 inches beyond the veins.
The veins at the War Baby Mine strike N 80 E, and dip 17 to 62 NW; they are found in a 33-feet-wide
zone and vary in thickness from 1 to 15 inches. The veins appear to belong to a single system that locally
branches in the hanging wall. The footwall is marked by slickensides that separate the lode from fresh
country rock. Sericitization and carbonate alteration predominate, but there is some pyritization and
chloritization occurs in the outer parts of the alteration zone (Ray, 1954). The veins are a continuation of
those at the Lucky Shot mine (AN002) although offset 600 to 700 feet along a prominent fault. The ore
mined through 1927 averaged 2.18 oz/ton Au (Ray, 1933).
The War Baby mine was consolidated with the Lucky Shot Mine (CH002) and mined by the same
company before 1942. In 2005, Full Metal Minerals Corp. began a intensive exploration that included the
Lucky Shot Mine, the War Baby Mine, and adjacent ground beyond either of them. The War Baby is now
only a block within that larger deposit that retains the name Lucky Shot. See the description of the Lucky
Shot Mine (AN002) for the status of the ground that was once the War Baby.
Alteration:
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Alaska Resource Data File AN003
The wall rocks are intensely altered near the veins. Adjacent to the veins, the wall rock is bleached to a
white or gray-green color, with much sericite, clay, and carbonates. There is an outer zone of propylitic
alteration.
Age of mineralization:
Late Cretaceous or younger; veins cut the Late Cretaceous Willow Creek Pluton.
Generic deposit model:
Deposit model:
Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a).
Deposit model number (After Cox and Singer, 1986 or Bliss, 1992):
36a
Production Status: Yes; medium
Site Status: Active
Workings/exploration:
Located in 1918, The War Baby Mine quickly saw the erection of a small mill. The first production from
the mine occurred in 1919 after two short tunnels and a crosscut were driven. Willow Creek Mines took
over the property in 1921. The War Baby was mined, with interruptions, from 1919 until 1940. There were
over 2,000 ft of underground workings on 3 levels. Ray (1933) reported that production from 1922 through
1927 was from a single stope measuring 175 by 250 ft with a maximum width of 10 to 12 ft. By 1950, the
mine had long since closed and the workings were inaccessible (Ray, 1954). The War Baby mine was
consolidated with the Lucky Shot Mine (CH002) and mined by the same company before 1942. In 2005,
Full Metal Minerals Corp. began a intensive exploration that included the Lucky Shot Mine, the War Baby
Mine, and adjacent ground beyond either of them. The War Baby is now only a block within that larger
deposit that retains the name Lucky Shot. See the description of the Lucky Shot (AN002) for the status of
the ground that was once the War Baby.
Production notes:
The War Baby Mine and the adjacent Lucky Shot Mine (AN002) were combined prior to WWII and both
mines were simultaneously operated by Willow Creek Mines. Stoll (1997) estimated that the total
production of the combined mines to 1951 was 252,000 ounces of gold.
Reserves:
See the Lucky Shot Mine (AN002) for the current status of the reserves.
Additional comments:
References:
Brooks, A.H., 1923, The Alaska mining industry in 1921: U.S. Geological Survey Bulletin 739-A, p. 1-50.
Brooks, A.H., 1925, Alaska's mineral resources and production, 1923: U.S. Geological Survey Bulletin 773-
A, p. 3-52.
Brooks, A.H., and Capps, S.R., 1924, The Alaska mining industry in 1922: U.S. Geological Survey Bulletin
755-A, p. 1-56.
Burleigh, R.E., 1987, A Stable Isotope, Fluid Inclusion and Ore Petrographic Study of the Gold Quartz
Veins in the Willow Creek Mining District. Masters Thesis, University of Alaska.
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Alaska Resource Data File AN003
Capps, S.R., 1940, Geology of the Alaska Railroad region: U.S. Geological Survey Bulletin 907, 201 p.
Chapin, Theodore, 1920, Lode developments in the Willow Creek district: U.S. Geological Survey Bulletin
712-E, p. 169-176.
Chapin, Theodore, 1921, Lode developments in the Willow Creek district: U.S. Geological Survey Bulletin
714-D, p. 201-206.
Cobb, E.H., 1972, Metallic mineral resources map of the Anchorage quadrangle, Alaska: U.S. Geological
Survey Miscellaneous Field Studies Map MF-409, 1 sheet, scale 1:250,000.
Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction
materials in the Anchorage quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-1095, 184 p.
Full Metal Minerals Corp., 2009, Full Metal announces signing of option agreement on its Lucky Shot
property:
http://www.fullmetalminerals.com/s/NewsReleases.asp?ReportID=371329&_Type=News&_Title=Full-
Metal-Announces-Signing-of-Option-Agreement-on-its-Lucky-Shot-Property (News release dated Nov 9,
2009).
Full Metal Minerals Corp., 2010a, Lucky Shot: http://www.fullmetalminerals.com/s/luckyshot.asp (as of
February 23, 2010).
Full Metal Minerals Corp., 2010b, Full Metal intersects 36.38 g/t Au over 7.3 meters at Lucky Shot;
underground exploration to commence:
http://www.fullmetalminerals.com/s/NewsReleases.asp?ReportID=384752&_Type=News&_Title=Full-
Metal-Intersects-36.38-gt-Au-over-7.3-Meters-at-Lucky-Shot-Underground.. (News release dated February
11, 2010).
Harlan, S.S, et al, 2003, Age and Cooling history of gold deposits and host rocks in the Willow Creek
Mining Districts), in Geological Society of America, Abstracts with Programs 35.6, p. 235.
Madden-McGuire, D.J., Silberman, M.L., and Church, S.E., 1988, Geologic Relationships, K-Ar Ages, and
Isotopic Data from the Willow Creek Gold Mining District, Southern Alaska, in Geologic Studies in Alaska
by the US Geological Survey, 1988, eds. J.H. Dover and J.P. Galloway, U.S. Geological Survey Bulletin
1903, 134 p.
McLeod, Robert, 2006, Lucky Shot gold project, Willow Creek Mining District, Alaska, 125 p. (posted on
www.sedar.com on September 13, 2006)
McLeod, Robert, 2006, Lucky Shot gold project, Willow Creek Mining District, Alaska: Technical report
prepared for Full Metal Minerals Ltd., 48 p. (posted on www.sedar.com, September 29, 2006.
Moffit, F.H., 1927, Mineral industry in Alaska in 1925: U.S. Geological Survey Bulletin 792-A, p. 1-39.
Ray, J.C., 1933, The Willow Creek gold-lode district, Alaska: U.S. Geological Survey Bulletin 849-C, p.
165-229.
Ray, R.G., 1954, Geology and ore deposits of the Willow Creek Mining district, Alaska: U.S. Geological
Survey Bulletin 1004, 86 p.
Silberman, M.L., O’Leary, R.M., Csejtey, B. Jr., Smith, J.G., and Connor, C.L., 1978, Geochemical
anomalies and Isotopic ages in the Willow Creek mining district, southwestern Talkeetna Mountains,
Alaska: U.S. Geological Survey Open-File Report 78-233.
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Alaska Resource Data File AN003
Smith, P.S., 1930, Mineral industry of Alaska in 1927: U.S. Geological Survey Bulletin 810-A, p. 1-64.
Smith, P.S., 1930, Mineral industry of Alaska in 1928: U.S. Geological Survey Bulletin 813-A, p. 1-72.
Smith, P.S., 1932, Mineral industry of Alaska in 1929, in Smith, P.S., and others Mineral resources of
Alaska, report on progress of investigations in 1929: U.S. Geological Survey Bulletin 824-A, p. 1-81.
Smith, P.S., 1933, Mineral industry of Alaska in 1930: U.S. Geological Survey Bulletin 836-A, p. 1-83.
Smith, P.S., 1933, Mineral industry of Alaska in 1931: U.S. Geological Survey Bulletin 844-A, p. 1-81.
Smith, P.S., 1934, Mineral industry of Alaska in 1932: U.S. Geological Survey Bulletin 857-A, p. 1-91.
Smith, P.S., 1934, Mineral industry of Alaska in 1933: U.S. Geological Survey Bulletin 864-A, p. 1-94.
Smith, P.S., 1936, Mineral industry of Alaska in 1934: U.S. Geological Survey Bulletin 868-A, p. 1-91.
Smith, P.S., 1937, Mineral industry of Alaska in 1935: U.S. Geological Survey Bulletin 880-A, p. 1-95.
Smith, P.S., 1938, Mineral industry of Alaska in 1936: U.S. Geological Survey Bulletin 897-A, p. 1-107.
Smith, P.S., 1939, Mineral industry of Alaska in 1937: U.S. Geological Survey Bulletin 910-A, p. 1-113.
Smith, P.S., 1939, Mineral industry of Alaska in 1938: U.S. Geological Survey Bulletin 917-A, p. 1-113.
Smith, P.S., 1941, Mineral industry of Alaska in 1939: U.S. Geological Survey Bulletin 926-A, p. 1-106.
Smith, P.S., 1942, Mineral industry of Alaska in 1940: U.S. Geological Survey Bulletin 933-A, p. 1-102.
Stevens, 2010, Lucky Shot project, Willow Creek Mining District, south-central Alaska: Technical Report
prepared for Harmony Gold Corp., 87 p. (posted on www.sedar.com, February 2, 2010).
Stoll, W.M., 1997, Hunting for gold in Alaska's Talkeetna Mountains 1897-1951--with a background sketch
of Alaska's great gold-lode camps: Greensburg, Pennsylvania, Henry Printing, 301 p.
Primary Reference:Stevens, 2010
Reporter(s): D.P. Bickerstaff (Contractor, U.S. Geological Survey); S.W. Huss (U. S. Geological Survey); D.J.
Grybeck (Contractor, U.S. Geological Survey)
Last report date: 2010-04-02
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Alaska Resource Data File AN004
Site name(s): Gold Bullion; New Bullion; Ready Bullion; Willow Creek
Mines Inc.
Site type:
Mine
ARDF no.: AN004
Latitude: 61.7898 Quadrangle:AND-7
Longitude:149.3292
Location description and accuracy:
Marked by adit symbols and the label 'Gold Bullion Mine' on the Anchorage D-7 1:63,360-scale
topographic map. The mine is near the top of the northwestern flank of Bullion Mountain, on the divide
between Willow and Craigie Creeks. It is near the southwest corner of section 29, T. 20 N., R. 1 E. of the
Seward Meridian.
Commodities:
Main: Au
Other: Cu, Hg
Ore minerals: Chalcopyrite, cinnabar, pyrite, secondary copper minerals
Gangue minerals: Quartz
Geologic description:
The Gold Bullion Mine was developed on one or more quartz veins 1.5 to 14 feet thick that are
intermittently exposed over 3,000 feet of strike length and have an average grade of about 1.7 ounces of
gold per ton (Capps, 1915). The nearly horizontal quartz veins at the Gold Bullion contain gold, small
amounts of pyrite, chalcopyrite, other sulfides, and are stained by copper carbonates. The veins cut tonalite
and quartz diorite of the Willow Creek pluton, which has been dated at 73-74 Ma (Stevens, 2010; Madden-
Mcguire and others, 1988). At least three normal faults are known to displace the veins (Stevens, 2010).
Visible slickensides and gouge are along the vein walls (Katz, 1911). Capps (1915) reported cinnabar along
cracks in quartz in one tunnel. According to Chapin (1920), most mining was on one vein that strikes N 10
E, and dips 14 NW. The ore averaged about 1.7 ounces of gold per ton (Ray, 1954). A K-Ar age from
muscovite in a quartz-sericite selvage adjacent to a gold-bearing vein nearby was 56 Ma, early Paleocene
(Silberman and others, 1978). Wall rock alteration is intense within a few inches of the veins, but seldom
extends more than 10 to 12 inches beyond the quartz vein. Sericitization and carbonate alteration
predominate, but there is some pyritization, and in the outer parts of the alteration zone the wall rock is
chloritized (Ray, 1954).
An adjacent property, the Ready Bullion vein was discovered during mining at the Gold Bullion Mine.
Workings were extended to it from the Ready Bullion in 1937 (Roehm, 1938; Stevens, 2010). The Ready
Bullion vein was 12 to 18 inches thick and could be traced for three claims. It was considered to be the
down-dip extension of the Gold Bullion.
In early 2010, the Gold Bullion Mine was part of a large block of claims that was being explored by the
Harmony Gold Corporation (Stevens, 2010). In 2014 Miranda Gold Corp. collected soil samples and vein
samples that identified significant anomalies potentially extending the fault limit of the Gold Bullion vein
and provided new targets for vein segments between the Murphy and Bullion Mountain veins (Linebarger,
2014).
Alteration:
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