Taurus

The Taurus is a molybdenum, copper, and gold mine located in Alaska.

About the MRDS Data:

All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.

Mine Info

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Site Name

Primary: Taurus
Secondary: East Taurus
Secondary: West Taurus

Commodity

Primary: Molybdenum
Primary: Copper
Primary: Gold

Location

State: Alaska
District: Fortymile

Land Status

Not available

Holdings

Not available

Workings

Not available

Ownership

Owner Name: Lodestar Explorations Ltd.
Percent: 100.0
Home Office: Canada
Info Year: 1992

Production

Not available

Deposit

Record Type: Deposit
Operation Category: Prospect
Operation Type: Unknown
Years of Production:
Organization:
Significant: Y

Physiography

Not available

Mineral Deposit Model

Model Name: Porphyry Cu-Mo

Orebody

Not available

Structure

Not available

Alterations

Alteration Type: L
Alteration Text: Hypogene alteration associated with mineralization includes argillic, potassic, phyllic, silicic, and propylitic alteration of varying intensities. A supergene leached cap, approximately 50 meters thick, exhibits strong argillic alteration over the East and West Taurus zones (Leriche, 1995).

Rocks

Not available

Analytical Data

Not available

Materials

Ore: Pyrite
Ore: Magnetite
Ore: Covellite
Ore: Chalcopyrite
Ore: Chalcocite
Ore: Molybdenite
Gangue: Tourmaline
Gangue: Sericite
Gangue: Quartz
Gangue: Fluorite

Comments

Comment (Reference): Primary Reference = Leriche, 1995

Comment (Geology): Age = Secondary biotite within the intrusion at the Taurus prospect has been dated by K-Ar techniques as approximately 57 +/- 2 Ma (Nokleberg and others, 1995).

Comment (Reserve-Resource): Reserves = In 1993, Noranda indicated that the East Taurus zone contains a 23 million ton reserve grading 0.3% Cu and 0.039% Mo (Leriche, 1995).

Comment (Workings): Workings / Exploration = Taurus prospect was staked in 1970 by International Minerals and Chemical Corporation during a reconnaissance geochemical survey. During the 1970's, geologic mapping, soil sampling, magnetometer and IP surveys, and 3060 meters of diamond and rotary drilling were done. In recent years, an airborne magnetic, electromagnetic, and resistivity survey, as well as 404 meters of reverse circulation drilling have been done (Leriche, 1995, p. 451). ? In 1987, Resource Associates of Alaska staked the Taurus and Bluff (TC005) prospects, but dropped both 2 years later. Noranda staked Taurus in 1993.

Comment (Ownership): HEMLO GOLD MINES LTD. DROPPED OPTION FOR 50% OF TAURUS IN 1992.

Comment (Exploration): Status = Active

Comment (Deposit): Model Name = Porphyry Cu-Mo deposit (Cox and Singer, 1986; model 21a)

Comment (Deposit): Other Comments = See also the Pushbush prospect (TC024) and the ASARCO prospect (TC001).

Comment (Geology): Geologic Description = The Taurus property is usually separated into two main zones: West Taurus and East Taurus. The property is underlain in part by a metamorphic basement complex of possible Late Precambrian or early Paleozoic age that consists of biotite gneiss, augen gneiss, biotite schist, and quartzite (Foster, 1970). Early Tertiary felsic rocks intrude the metamorphic rocks. Secondary biotite within the intrusion at the Taurus prospect has been dated by K-Ar techniques to be approximately 57 +/- 2 Ma (Nokleberg and others, 1995). ? Two major faults have been identified on the property. The Tourmaline fault strikes northeasterly and appears to have left-lateral movement with a possible displacement of up to 6.5 km. The McCord Creek fault trends easterly across the claims. Porphyry intrusions, which host mineralization at the East and West Taurus zones, are located near the McCord Creek fault, suggesting that it controlled their emplacement. Many northeast trending linears have been interpreted using satellite images and topographic maps (Leriche, 1995, p. 452).? the Taurus porphyry copper-type mineralization appears to be related to a group of widespread, small bodies of early Tertiary, quartz monzonite porphyry, quartz latite, feldspar-quartz porphyry, intrusive breccia, quartz porphyry and dacite porphyry. Intrusive breccia crops out along the southern border of an altered Upper Cretaceous granodioritic pluton on the eastern side of the property. Quartz monzonite porphyry occurs along the southern contacts of the altered granodiorite and of intrusive breccia in the central part of the property (Leriche, 1995, p. 452). ? the alteration at the East Taurus zone consists of an upper leached cap underlain by supergene and hypogene zones. The leached cap varies from 40 to 50 meters in depth, and shows pervasive argillic alteration due to groundwater leaching. Other alteration types in the leached cap consist of pervasive silicification, quartz-sericite, and quartz-magnetite alteration. Supergene and hypogene zones are accompanied by phyllic, silicic, propylitic, and potassic alteration (Leriche, 1995, p. 453).?Mineralization in the leached cap at East Taurus consists of minor remnant pyrite, chalcopyrite, and molybdenite in quartz stockworks and silicified zones. The supergene zone varies in thickness from 30 meters to 53 meters. Mineralization in it consists of chalcocite, covellite, pyrite, chalcopyrite, and molybdenite. Chalcocite appears in fractures and within quartz veinlets. In the lower hypogene zone, mineralization is pyrite, chalcopyrite, and molybdenite as disseminations along fractures and in the center of quartz veinlets (Leriche, 1995, p. 453).? Mineralization in the West Taurus area consists of pyrite and subordinate chalcopyrite, covellite, chalcocite, malachite, and azurite. Molybdenite is found in quartz-filled fractures in the sericitically altered, quartz latite unit. Chalcopyrite and molybdenite are found as fracture fillings in close proximity to the Tourmaline and McCord Creek faults (Leriche, 1995, p. 454).? the majority of drilling conducted on the property has been done in the East Taurus zone. In 1993, Noranda calculated preliminary reserves of 23 million tons grading 0.3% Cu and 0.039% Mo. Drill samples collected in the 1970's were not assayed for gold, but later analyses of part of the core reveals some elevated values in gold (Leriche, 1995, p. 455).? Resource Associates of Alaska re-staked the Taurus and Bluff (TC005) prospects in 1987 and did some soil geochemistry. They dropped both properties two years later. They probably analyzed for gold and may not have found enough to continue holding the property.

References

Reference (Deposit): Gill, R., 1977, Geology and mineral deposits of the southwest quarter of the Tanacross D-1 quadrangle, Alaska: Golden, Colorado School of Mines, M.Sc. thesis, 129 p.

Reference (Deposit): Eberlein, G.D., Chapman, R.M., Foster, H.L., and Gassaway, J.S., 1977, Map and table describing known metalliferous and selected nonmetalliferous mineral deposits in central Alaska: U.S. Geological Survey Open-File Report 77-168-D, 132 p., 1 map, scale 1:1,000,000.

Reference (Deposit): Singer, D.A., Csejtey, Bela, Jr., and Miller, R.J., 1978, Map and discussion of the metalliferous and selected nonmetalliferous mineral resources of the Talkeetna Mountains quadrangle, Alaska: U.S. Geological Survey Open-file Report 78-588-Q, 33 p., 1 plate, scale 1:250,000.

Reference (Deposit): Foster, H.L., 1970, Reconnaissance geologic map of the Tanacross quadrangle, Alaska: U.S. Geological Survey Miscellaneous Geological Investigations Map I-593, 1 sheet, scale 1:250,000.

Reference (Deposit): Nokleberg, W.J., Bundtzen, T.K., Brew, D.A., and Plafker, G., 1995, Metallogenesis and tectonics of porphyry copper and molybdenum (gold, silver) and granitoid-hosted gold deposits of Alaska: Canadian Institute of Mining and Metallurgy Special Volume 46, p. 103-141.

Reference (Deposit): Cobb, E.H., and Eberlein, G.D., 1980, Summaries of data on and lists of references to metallic and selected nonmetallic mineral deposits in the Big Delta and Tanacross quadrangles, Alaska: U.S. Geological Survey Open-File Report 80-1086, 77 p.

Reference (Deposit): Nokleberg, W.J., Bundtzen, T.K., Berg, H.C., Brew, D.A., Grybeck, D.J., Robinson, M.S., Smith, T.E., and Yeend, W., 1987, Significant metalliferous lode deposits and placer districts of Alaska: U.S. Geological Survey Bulletin 1786, 104 p.

Reference (Deposit): Leriche, P.D., 1995, Taurus copper-molybdenum porphyry deposit, east-central Alaska: in Schroeter, T.G., ed., Porphyry Deposits of the Northwestern Cordillera: Canadian Institute of Mining, Metallurgy, and Petroleum Special Volume 46, p. 451-457.

Reference (Reserve-Resource): NORTHERN MINER, 3/9/92
Pages: 17

Reference (Deposit): THE MINING RECORD, 4/7/93
Pages: 5

Reference (Deposit): Newberry, R.J., Layer, P.W., Burleigh, R.E., and Solie, D.N., 1996, New 40Ar/39Ar dates for intrusions and mineral prospects in the eastern Yukon-Tanana terrane, Alaska - Regional patterns and significance, in Gray, J.E., and Riehle, J.R., eds., Geological Studies in Alaska by the U.S. Geological Survey, 1996: U.S. Geological Survey Professional Paper 1595, p. 131-159.

Reference (Ownership): NORTHERN MINER, 5/4/92
Pages: 1

Reference (Deposit): Singer, D.A., Curtin, G.C., and Foster, H.L., 1976, Mineral resources map of the Tanacross Quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies 767-E, 1 sheet, scale 1:250,000.

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