Silver Coin

Occurrence in Alaska, United States with commodities Copper, Lead

Geologic information

Identification information

Deposit ID 10000217
MRDS ID A010252
Record type Site
Current site name Silver Coin

Geographic coordinates

Geographic coordinates: -130.1687, 56.07755 (WGS84)
Relative position The Silver Coin occurrence is in Section 7 at an elevation of about 4150 feet on a south-facing mountainside about 0.4 mile east of upper Ibex Creek (Elliott and Koch, 1981, p. 14, loc. 50). The location is probably accurate within about a quarter of a mile.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Lead Primary

Materials information

Materials Type of material
Chalcopyrite Ore
Galena Ore
Malachite Ore
Pyrite Ore
Quartz Gangue

Alteration

  • (Local) Minor oxidation of chalcopyrite to malachite.

Mineral occurrence model information

Model code 85
USGS model code 22c
Deposit model name Polymetallic veins
Mark3 model number 46

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
    Rock unit name Texas Creek
    Rock description Texas Creek
  • Host or associated Host
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite

Nearby scientific data

(1) -130.1687, 56.07755

Comments on the geologic information

  • Geologic Description = The country rock in the area of the Silver Coin occurrence is Triassic Texas Creek Granodiorite, which regionally underlies and locally intrudes pelitic metasedimentary and subordinate andesitic metavolcanic strata of the Jurassic or older Mesozoic Hazelton Group; and the Eocene Hyder Quartz Monzonite, which intrudes the Hazelton and Texas Creek rocks (Smith, 1977; Koch, 1996).? Buddington (1925, p. 90; 1929, p. 95) describes the deposit as a quartz fissure vein up to about 10 feet thick and 50 feet long in a shear zone in granodiorite. The northern 25 feet of the vein contains a shoot as much as 5 feet thick of massive galena, accompanied by a little pyrite and chalcopyrite. The remainder of the vein is barren. A little malachite occurs on shear surfaces in the granodiorite footwall of the ore shoot.? Lead-isotope studies of galena from the Silver Coin occurrence (Maas and others, 1995, p. 229-248) indicate that the deposit is Eocene in age, contemporaneous with emplacement of the Hyder Quartz Monzonite.
  • Age = Lead-isotope studies of galena from the Silver Coin occurrence (Maas and others, 1995, p. 229-248) indicate that the deposit is Eocene in age, contemporaneous with emplacement of the Hyder Quartz Monzonite.

Economic information

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Hyder

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A010252
USGS Alaska Resource Data File ARDF BC050

Bibliographic references

  • Deposit

    Buddington, A.F., 1925, Mineral investigations in southeastern Alasaka: U.S. Geological Survey Bulletin 773, p. 71-139.

  • Deposit

    Buddington, A.F., 1929, Geology of Hyder and vicinity, southeastern Alaska, with a reconnaissance of Chickamin River: U.S. Geological Survey Bulletin 807, 124 p.

  • Deposit

    Smith, J.G., 1977, Geology of the Ketchikan D-1 and Bradfield Canal A-1 quadrangles, Alaska: U.S. Geological Survey Bulletin 1425, 49 p.

  • Deposit

    Elliott, R.L., and Koch, R.D., 1981, Mines, prospects, and selected metalliferous mineral occurrences in the Bradfield Canal quadrangle, Alaska: U.S. Geological Survey Open-File Report 81-728-B, 23 p., 1 sheet, scales 1:250,000 and 1:63,360.

  • Deposit

    Maas, K.M., Bittenbender, P E., and Still, J.C., 1995, Mineral investigations in the Ketchikan mining district, southeastern Alaska: U.S. Bureau of Mines Open-File Report 11-95, 606 p.

  • Deposit

    Koch, R.D., 1996, Reconnaissance geologic map of the Bradfield Canal quadrangle, southeastern Alaska: U.S. Geological Survey Open-File Report 81-728-A, 35 p., 1 sheet, scale 1:250,000.

Comments on the references

  • Primary Reference = Buddington, 1929

General comments

Subject category Comment text
Deposit Model Name = Polymetallic vein
Deposit Other Comments = Site probably originally staked in 1923

Reporter information

Type Date Name Affiliation Comment
Reporter 17-MAY-1998 H. C. Berg U.S. Geological Survey