Breen West (Bison)

Past Producer in Alaska, United States with commodities Gold, Antimony

Geologic information

Identification information

Deposit ID 10094065
MRDS ID A012804
Record type Site
Current site name Breen West (Bison)

Geographic coordinates

Geographic coordinates: -165.3369, 64.75707 (WGS84)
Relative position The Breen West mine is on the Bison Lode claim, which was patented in 1924. It is at an elevation of about 800 to 1,000 feet on the southwest-facing slope of the ridge between Cold and Manila Creeks and accessible by foot or ATV from a trail which starts in Steep Creek. It is about one-half mile southeast of an unnamed occurrence (NM088) that was mistakenly called Breen West by Hummel (1962 [MF 248]). The Breen West mine is about 1,000 feet west of the vein outcrops on the My Best Lode claim (U.S. Mineral Survey No. 1380) of the Sliscovich mine (NM086). This location is within 500 feet of the surface workings, heavy quartz-stibnite float, and the main discovery cuts on the Bison Lode claim (U.S. Mineral Survey No. 1391). This is locality 1 of Hummel (1962 [MF 248]) and locality 27 of Cobb (1972 [MF 463], 1978 [OFR 78-93]) who apparently mistakenly identified it as Breen East.
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Geographic areas

Country State
United States Alaska


Commodity Importance
Gold Primary
Antimony Primary

Materials information

Materials Type of material
Arsenopyrite Ore
Gold Ore
Stibnite Ore
Calcite Gangue
Quartz Gangue


  • (Local) Disseminated arsenopyrite in sheared metasedimentary schist.

Mineral occurrence model information

Model code 180
USGS model code 27d
Deposit model name Simple Sb (veins, pods, etc)
Model code 273
USGS model code 36a
Deposit model name Low-sulfide Au-quartz vein
Mark3 model number 27

Host and associated rocks

  • Host or associated Host
    Rock type Metamorphic Rock > Schist

Nearby scientific data

(1) -165.3369, 64.75707

Comments on the geologic information

  • Geologic Description = The Breen West deposit, as exposed on the Bison Lode claim, includes quartz-stibnite veins with some calcite in metasedimentary schist. The quartz-stibnite veins are like those at the adjacent Sliscovich mine (NM086). The metasedimentary schist host rock to the quartz-stibnite veins is also mineralized. A thin zone of metasedimentary schist (calc-schist, quartz-mica schist, and schistose marble) separates feldspathic schist or orthogneiss from underlying massive marble (D. Simpson, Bear Creek Mining Company, written communication, 1984). The lower 5 to 30 feet of the metasedimentary schist zone is sheared and brecciated. Geologic studies and open-hole rotary drilling carried out by Mapco in 1982 and 1983 suggested that mineralization could be stratabound in the metasedimentary schist. Mapco drilled a total of 32 open-hole rotary holes and defined an area of about 200 feet by 600 feet that contained stibnite and about 0.2 ounce of gold per ton (Stevens, 1991). Bear Creek Mining Company took over the property in 1984 and drilled four core holes that totaled 1,423 feet in length. The drilling appeared to confirm low-grade mineralization, about 0.01-0.03 ounce of gold per ton, in the metasedimentary schist. This drilling did not confirm Mapco's best intercept of 0.125 ounces of gold per ton between 155 and 173 feet in drill hole MD-DH-3. A Bear Creek Mining core hole twinned MD-DH-3 but found only 0.024 ounce of gold per ton gold over 25 feet in the same interval. D. Simpson (Bear Creek Mining Company, written communication, 1984) concluded that high grade gold-stibnite mineralization was localized along east-west-trending, high-angle structures, but that there was also epigenetic psuedo-stratabound mineralization in the metasedimentary schist. Arsenopyrite appeared to be characteristic constituent of the sheared, gold-bearing schist.? In a detailed soil geochemistry program, Bear Creek Mining found as much as 3,300 ppb gold, 7,300 ppm antimony and greater than 1,000 ppm arsenic in soils over the Breen West mine. High-grade samples from semi-massive stibnite veins contained as much as 2.85 ounces of gold per ton. The vein targets, although of very high grade and as much as 4 feet thick, were not of interest to Bear Creek Mining, who returned the property to its owners. The surface workings on the Breen West mine are the probable source of 14 tons of ore that were produced in about 1920. Reportedly, only gold was paid for, although the ore contained about 10 percent antimony (Anderson, 1947).? the Breen West mine is in metasedimentary schist between a marble-rich section and an overlying feldspathic unit mapped as a granodioritic sill or orthogneiss by Hummel (1962 [MF248]). It appears to be within the massive marble unit as mapped by Bundtzen and others (1994); in this area, Hummel's mapping seems to more correctly represent the geology. Subsequent workers have mapped the feldspathic unit as chlorite-feldspar schist and
  • Geologic Description = have proposed that it is an intermediate volcanic unit (D. Simpson, Bear Creek Mining Company, written communication, 1984).? the metamorphic rocks are part of the Nome Group, which was derived from Proterozoic to early Paleozoic protoliths (Till and Dumoulin, 1994). The Nome Group underwent regional blueschist facies metamorphism in the Late Jurassic or Early Cretaceous (Sainsbury, Coleman, and Kachadoorian, 1970; Forbes and others, 1984; Thurston, 1985; Armstrong and others, 1986; Hannula and McWilliams, 1995). The blueschist facies rocks were recrystallized to greenschist facies or higher metamorphic grades in conjunction with regional extension, crustal melting, and magmatism in the mid-Cretaceous (Hudson and Arth, 1983; Miller and Hudson, 1991; Miller and others, 1992; Dumitru and others, 1995; Hannula and others, 1995; Hudson, 1994; Amato and others, 1994; Amato and Wright, 1997, 1998). Lode gold-antimony mineralization on Seward Peninsula is mostly related to the higher temperature metamorphism in the mid-Cretaceous (Apodoca, 1994; Ford, 1993 [thesis]; Ford and Snee, 1996; Goldfarb and others, 1997).
  • Age = Mid-Cretaceous; controlled by structures that post-date regional metamorphism; may be same age as some lode gold deposits of Seward Peninsula.

Economic information

Economic information about the deposit and operations

Development status Past Producer
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Nome

Comments on the production information

  • Production Notes = The surface workings on the Breen West mine are the probable source of 14 tons of ore that were produced in about 1920. Reportedly only gold was paid for, although the ore contained about 10 percent antimony (Anderson, 1947).

Comments on the workings information

  • Workings / Exploration = A lode was found at the nearby Sliscovich claim by 1905. Discoveries were subsequently made on the nearby Bison and Haymaker claims that were patented to Henry P. Breen in 1924. The area was probably actively prospected in World War II for strategic minerals. Some work on the Breen claims was done by GCO Minerals in 1968 and 1969. Extensive work was begun by Mapco in 1981; in 1982 and 1983 Mapco drilled 32 open-hole rotary drill holes on a stratabound target in metasedimentary schist. Bear Creek Mining Company optioned the property in 1984 and conducted geologic mapping, geochemical sampling, and a 4-hole core drill program.?They concluded that there was weak pseudo-stratabound mineralization, but that high-grade stibnite-gold veins were steeply dipping and cross-cut the metamorphic structure. BHP Minerals conducted geologic, geochemical, and geophysical studies, including a DIGHEM airborne survey, between 1988 and 1990 in the area. They found a very large gold and antimony anomaly in soils and also confirmed a possible high-grade vein trend in the Breen and Sliscovich areas. BHP pulled out in 1991. Kennecott Exploration Company conducted regional studies in 1995, including re-examination of the Breen and Sliscovich lodes (NM084, NM085, NM086).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A012804
USGS Alaska Resource Data File ARDF NM087

Bibliographic references

  • Deposit

    Anderson, Eskil, 1947, Mineral occurrences other than gold deposits in northwestern Alaska: Alaska Territorial Division of Mines Pamphlet 5-R, 48 p.

  • Deposit

    Hummel, C.L., 1962, Preliminary geologic map of the Nome D-1 quadrangle, Seward Peninsula, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-248, 1 sheet, scale 1:63,360.

  • Deposit

    Sainsbury, C.L., Coleman, R.G., and Kachadoorian, Reuben, 1970, Blueschist and related greenschist faces rocks of the Seward Peninsula, Alaska, in Geological Survey research 1970: U.S. Geological Survey Professional Paper 700-B, p. B33-B42.

  • Deposit

    Cobb, E.H., 1972, Metallic mineral resources map of the Nome quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-463, 2 sheets, scale 1:250,000.

  • Deposit

    Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Nome quadrangle, Alaska: U.S. Geological Survey Open-File report 78-93, 213 p.

  • Deposit

    Hudson, T.L., and Arth, J. G., 1983, Tin-granites of Seward Peninsula, Alaska: Geological Society of America Bulletin, v. 94, p. 768-790.

  • Deposit

    Forbes, R.B., Evans, B.W., and Thurston, S.P., 1984, Regional progressive high-pressure metamorphism, Seward Peninsula, Alaska: Journal of Metamorphic Geology, v. 2, p. 43-54.

  • Deposit

    Thurston, S.P., 1985, Structure, petrology, and metamorphic history of the Nome Group blueschist terrane, Salmon Lake area, Seward Peninsula, Alaska: Geological Society of America Bulletin, v. 96, p. 600-617.

  • Deposit

    Armstrong, R.L., Harakal, J.E., Forbes, R.B., Evans, B.W., and Thurston, S.P., 1986, Rb-Sr and K-Ar study of metamorphic rocks of the Seward Peninsula and southern Brooks Range, Alaska, in Evans, B.W., and Brown, E.H., eds., Blueschists and eclogites: Geological Society of America Memoir 164, p. 184-203.

  • Deposit

    Miller, E.L., and Hudson, T.L., 1991, Mid-Cretaceous extensional fragmentation of a Jurassic-Early Cretaceous compressional orogen, Alaska: Tectonics, v. 10, p. 781-796.

  • Deposit

    Stevens, D.L., 1991, Mt. Distin prospect, Seward Peninsula, Alaska: Unpublished report for Bering Straits Native Corporation, Nome, Alaska, 22 p.

  • Deposit

    Miller, E.L., Calvert, A.T., and Little, T.A., 1992, Strain-collapsed metamorphic isograds in a sillimanite gneiss dome, Seward Peninsula, Alaska: Geology, v. 20, p. 487-490.

  • Deposit

    Ford, R.C., 1993, Geology, geochemistry, and age of gold lodes at Bluff and Mt. Distin, Seward Peninsula, Alaska: Golden, Colorado School of Mines, Ph.D. dissertation, 302 p.

  • Deposit

    Apodoca, L. E., 1994, Genesis of lode gold deposits of the Rock Creek area, Nome mining district, Seward Peninsula, Alaska: Boulder, Colorado, University of Colorado, Ph.D. dissertation, 208 p.

  • Deposit

    Hudson, T.L. 1994, Crustal melting events in Alaska, in Plafker, G., and Berg, H. C., eds., The Geology of Alaska: Boulder, Colorado, Geological Society of America, The Geology of North America, v. G-1, p. 657-670.

  • Deposit

    Till, A.B., and Dumoulin, J.A, 1994, Geology of Seward Peninsula and St. Lawrence Island, in Plafker, G., and Berg, H.C., eds., The Geology of Alaska: Geological Society of America, The Geology of North America, DNAG, v. G-1, p. 141-152.

  • Deposit

    Amato, J.M., Wright, J.E., Gans, P.B., and Miller, E.L., 1994, Magmatically induced metamorphism and deformation in the Kigluaik gneiss dome, Seward Peninsula, Alaska: Tectonics, v. 13, p. 515-527.

  • Deposit

    Dumitru, T.A., Miller, E.L., O'Sullivan, P.B., Amato, J.M., Hannula, K.A., Calvert, A.T., and Gans, P.B., 1995, Cretaceous to Recent extension in the Bering Strait region, Alaska: Tectonics, v. 14, p. 549-563.

  • Deposit

    Hannula, K.A., Miller, E.L., Dumitru, T.A., Lee, Jeffrey, and Rubin, C.M., 1995, Structural and metamorphic relations in the southwest Seward Peninsula, Alaska; Crustal extension and the unroofing of blueschists: Geological Society of America Bulletin, v. 107, p. 536-553.

  • Deposit

    Hannula, K.A., and McWilliams, M.O., 1995, Reconsideration of the age of blueschist facies metamorphism on the Seward Peninusla, Alaska, based on phengite 40Ar/39Ar results: Journal of Metamorphic Geology, v. 13, p. 125-139.

  • Deposit

    Ford, R.C., and Snee, L.W., 1996, 40Ar/39Ar thermochronology of white mica from the Nome district, Alaska: The first ages of lode sources to placer gold deposits in the Seward Peninsula: Economic Geology, v. 91, p. 213-220.

  • Deposit

    Goldfarb, R.J., Miller, L.D., Leach, D.L., and Snee, L.W, 1997, Gold deposits in metamorphic rocks in Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral deposits of Alaska: Economic Geology Monograph 9, 482 p.

  • Deposit

    Amato, J.M., and Wright, J.E., 1997, Potassic mafic magmatism in the Kigluaik gneiss dome, northern Alaska -- A geochemical study of arc magmatism in an extensional tectonic setting: Journal of Geophysical Research, v. B102, no. 4, p. 8065-8084.

  • Deposit

    Amato, J.M., and Wright, J.E., 1998, Geochronologic investigations of magmatism and metamorphism within the Kigluaik Mountains gneiss dome, Seward Peninsula, Alaska, in Clough, J.G., and Larson, Frank, eds., Short Notes on Alaskan Geology 1997: Alaska Division of Geological and Geophysical Surveys Professional Report 118a, p. 1-21.

  • Deposit

    Bundtzen, T.K., Reger, R.D., Laird, G.M., Pinney, D.S., Clautice, K.H., Liss, S.A., and Cruse, G.R., 1994, Progress report on the geology and mineral resources of the Nome mining district: Alaska Division of Geological and Geophysical Surveys, Public Data-File 94-39, 21 p., 2 sheets, scale 1:63,360.

Comments on the references

  • Primary Reference = Stevens, 1991; this report

General comments

Subject category Comment text
Deposit Model Name = Disseminated, gold-bearing sulfide mineralization in calcareous metasedimentary schist; simple Sb deposits; low sulfide, Au-quartz vein? (Cox and Singer, 1986; model 27d and 36a).
Deposit Model Number = 27d?, 36a?
Deposit Other Comments = Most of the area is controlled by Bering Straits Regional Native Corporation.

Reporter information

Type Date Name Affiliation Comment
Reporter 22-OCT-99 Hawley, C.C. Hawley Resource Group
Reporter 22-OCT-99 Travis L. Hudson Hawley Resource Group