Boob Creek

Mine, Active

Commodities and mineralogy

Main commodities Au
Other commodities Ag; Hg; Pt; Sn
Ore minerals cassiterite; cinnabar; gold; magnetite; platinum; pyrite
Gangue minerals garnet; quartz

Geographic location

Quadrangle map, 1:250,000-scale OP
Quadrangle map, 1:63,360-scale B-3
Latitude 63.3312
Longitude -157.0029
Nearby scientific data Find additional scientific data near this location
Location and accuracy Boob Creek is is a north-flowing tributary to Mastodon Creek. For this record, the site is plotted about 2.6 miles southeast of the site of Tolstoi, at the south boundary of sec. 8, T. 25 S., R. 10 E. The coordinates mark the approximate midpoint of placer mining along Boob Creek, near a cabin marked on the U.S. Geological Survey Ophir B-3 topographic map. Boob Creek is locality 2 of Cobb (1972 [MF 367]). The location is accurate.

Geologic setting

Geologic description

The country rocks in the Boob Creek area consist of Cretaceous sandstone and shale, Jurassic greenstone and cherty tuff, Paleozoic limestone and metamorphic rocks, Cretaceous or Tertiary monzonite intrusions, and an ultramafic complex at Mt. Hurst (Chapman and others, 1985; Roberts, 1984; Hawley and others, 1991; Bundtzen and Miller, 1997). The layered ultramafic rocks exposed at Mt. Hurst may be present in the Boob Creek area and may be the source of platinum-group metals at Boob Creek.
Placer gold and platinum-group metals occur in gravels approximately 2 to 4 feet thick, buried beneath 25-30 feet of muck (Harrington, 1919). It is also likely that additional buried ancient stream channels exist in the Boob Creek area that may contain gold and platinum. Harrington (1919) reports that platinum made up about 1% of the metal produced from Boob Creek. Concentrates also contain cinnabar, magnetite, pyrite, garnet, magnesiochromite, hematite, zircon, anthophyllite, diopside, and obsidian (Harrington, 1919). Microprobe analyses of platinum grains from Boob Creek show that the grains are mostly ferrian platinum, with lesser amounts of osmium iridium. Some inclusions of rhodium and iridium sulfide (prassoite) are also present, as well as martite and platinum and palladium arsenides and sulfides (Tom Bundtzen, undated unpublished data). Gold at Boob Creek is approximately 902 fine, with 86 parts silver and 12 parts impurities (Bundtzen and others, 1987).
Gold was discovered along Boob Creek in 1916, and in the following year 3,100 ounces of gold and 30 ounces of platinum were recovered (Harrington, 1919). Mining, exploration, and development along Boob Creek continued at a reduced rate intermittently until the mid 1960s. Boob Creek was re-staked during the 1980s and sporadic exploration and small-scale mining have occurred since that time (Dashevsky, 2001). Shafts and drifts were hand-dug during the 1980s and 1990s; some recovery of gold, platinum, and fossil ivory was reported (Hawley and Buxton, 1991; Bundtzen and others, 1992; Dashevsky, 2001). One ounce of platinum was recovered during 1995 exploration work (Bundtzen and others, 1996).
Conservative production estimates from Boob Creek are 3,170 ounces of gold and 320 ounces of silver (Bundtzen and others, 1987). Most of this is probably from the first year after discovery. More recent production figures are not available.
Also see OP008, 009, 012, and 020.
Geologic map unit (-157.005285225939, 63.3305626610087)
Mineral deposit model Placer Au-Pt (Cox and Singer, 1986; model 39 a)
Mineral deposit model number 39a
Age of mineralization Quaternary. The source of the placer gold at Boob Creek may be the Cretaceous or Tertiary monzonite in the area; the source of the platinum is probably ultramafic rocks, such as those at Mt. Hurst.

Production and reserves

Workings or exploration Gold was discovered along Boob Creek in 1916, and in the following year 3,100 ounces of gold and 30 ounces of platinum were recovered (Harrington, 1919). In 1916, a pay streak was reported as 75 to 100 feet wide and traceable through 5 claims (Hawley and Buxton, 1991). In 1918, the principal owner of the Boob Creek claims, J.E. Riley, was murdered, and mining, exploration, and development along Boob Creek continued at a reduced rate intermittently until the mid-1960s. Boob Creek was re-staked during the 1980s and sporadic exploration and small-scale mining have occurred since that time (S. Dashevsky, 2001). Although over 100 shafts have been sunk into the Boob Creek area, locations are documented only for shafts sunk within the last 20 years (Hawley and Buxton, 1991; Dashevsky, 2001). Shafts and drifts were hand-dug during the 1980s and 1990s; some recovery of gold, platinum, and fossil ivory was reported (Hawley and Buxton, 1991; Bundtzen and others, 1992; Dashevsky, 2001). Ground-penetrating radar studies were conducted in the Boob Creek area in 2000, in an attempt to locate buried auriferous channels (3D Mining, unpublished data, 2000).
Indication of production Yes; small
Production notes
Conservative production estimates from Boob Creek are 3,170 ounces of gold and 320 ounces of silver (Bundtzen and others, 1987). Most of this is probably from the first year after discovery. More recent production figures are not available.
Although over 100 shafts have been sunk into the Boob Creek area, locations are documented only for shafts sunk within the last 20 years (Hawley and Buxton, 1991; Dashevsky, 2001). Two shafts were dug during 1984, and nearly 4 ounces of gold, 11 grains of platinum, and a 225-pound tusk of fossil ivory, as well as other ivory and bone items were recovered. In 1987, 3 shafts and 4 drifts were completed, and 1.62 ounces of gold and a trace of platinum were recovered. During 1989, 1 shaft and 3 drifts were sunk, and 2.69 ounces of gold, 6.75 grains of platinum, and approximately 15 pounds of fossil ivory were recovered (Hawley and Buxton, 1991). In 1991, further exploration work was done on Boob Creek and gold and platinum were recovered (Bundtzen and others, 1992). Further exploration took place in 1995; minor gold and 1 ounce of platinum were recovered (Bundtzen and others, 1996).

References

MRDS Number A015001; M045397

References

Dashevsky, S.S., 2001, Tolstoi project (Au, Pt) Innoko district, Alaska: Unpublished report for 3D Mining, Inc., 8 p.
Hawley, C.C., and Buxton, C.L., 1991, Boob Creek placer prospect, western Alaska: Hawley Resource Group, unpublished company report, 13 p.
Smith, S.S., 1917, The mining industry in the Territory of Alaska during the calendar year 1916: U.S. Bureau of Mines Bulletin 153, 89 p.
Reporters C.E. Cameron
Last report date 8/7/2001