Silver Shield

Prospect in Alaska, United States with commodities Silver, Lead, Gold, Barium-Barite, Copper

Geologic information

Identification information

Deposit ID 10001149
MRDS ID A011844
Record type Site
Current site name Silver Shield
Related records 10233886

Geographic coordinates

Geographic coordinates: -144.03374, 62.75079 (WGS84)
Relative position The Silver Shield prospect (Cobb, 1979, p. 25) is about 1.2 mile east of the junction of Ahtell and Flat Creeks at an elevation of about 3,300 feet. The prospect is locality 14 of Richter and Matson (1972), and number 13 of MacKevett and Holloway (1977). The location is accurate to 500 feet. It is about on the center of the east side of the NE1/4, section 11, T. 11 N., R. 7 E., Copper River Meridian.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Lead Primary
Gold Secondary
Barium-Barite Secondary
Copper Secondary

Materials information

Materials Type of material
Barite Ore
Cerussite Ore
Galena Ore
Limonite Ore
Pyrite Ore
Tetrahedrite Ore
Calcite Gangue
Quartz Gangue

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 Volcanic Rock (Aphanitic) > Pyroclastic Rock > Tuff
    Rock unit name Tetelna Formation
    Rock description Tetelna Formation
    Stratigraphic age (youngest) Late Permian
    Stratigraphic age (youngest) Late Permian
    Stratigraphic age (youngest) Late Permian
    Stratigraphic age (youngest) Late Permian
  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Sandstone
    Rock unit name Tetelna Formation
    Rock description Tetelna Formation

Nearby scientific data

(1) -144.03374, 62.75079

Comments on the geologic information

  • Geologic Description = The Silver Shield prospect is in a vertical fault zone that separates mixed sedimentary-volcanic rocks to the north and volcanic rocks to the south. The fault strikes N55E. The rocks are mapped as Pennsylvanian to Permian, Tetelna Formation by Richter (1964; 1966).? the vein was discovered by the Alaska Division of Mines and Minerals in 1963 (Richter, 1964) It is poorly exposed but appears to be a limonite-stained quartz vein about five-feet thick with local concentrations of coarse galena, that cuts locally pyritic, sedimentary and volcanic rock. A 3-foot channel sample of the vein contained a trace of gold, 19.8 ounces of silver per ton, and 1.6 percent lead. Another sample contained 21 ounces of silver per ton, and 2.4 percent lead.? Subsequent private exploration determined that the quartz occurs as veins and pods in a 35-foot vertical, fault zone. The quartz veins locally contain segregations of massive barite and lesser amounts of calcite. Galena is disseminated in crystals as much an inch across; cerussite, presumably after galena, also occurs in the veins. Some of the quartz was vuggy and argentiferous tetrahedrite occurs locally in the vuggy zones. Selected samples of tetrahedrite-rich vein material contain as much as 400 ounces of silver per ton (Richter, 1966).
  • Age = Emplaced subseqent to or is related to the border phase of the Pennsylvanian to Permian, Ahtell pluton.

Economic information

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Chistochina

Comments on the workings information

  • Workings / Exploration = The deposit was discovered in 1963 by the Alaska Division of Mines and Minerals and was announced in 1964. It was staked soon afterwards. The deposit has been explored by open cuts.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A011844
USGS Alaska Resource Data File ARDF GU014

Bibliographic references

  • Deposit

    Richter, D.H., 1964, Geology and mineral deposits of the Ahtell Creek area, Slana District, south-central Alaska: Alaska Division of Geological and Geophysical Surveys Geologic Report 6, 17 p., 1 sheet, scale 1:31,680.

  • Deposit

    Richter, D.H., 1966, Geology of the Slana district on south-central Alaska: Alaska Division of Geological and Geophysical Surveys Geological Report 2l, 36b p., 3 sheets, scale 1:63,360.

  • Deposit

    Richter, D.H., and Matson, N.A., 1968, Distribution of gold and some base metals in the Slana area, eastern Alaska Range, Alaska: U.S. Geological Survey Circular 593, 20 p.

  • Deposit

    Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Gulkana quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-1247, 36 p.

  • Deposit

    Richter, D.H., and Matson, N.A., Jr., 1972, Metallic mineral resources map of the Gulkana quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-419, 1 sheet, scale 1:250,000.

  • Deposit

    MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000.

Comments on the references

  • Primary Reference = Richter, 1966

General comments

Subject category Comment text
Deposit Model Name = Polymetallic vein (Cox and Singer, 1986; model 22c)

Reporter information

Type Date Name Affiliation Comment
Reporter 05-DEC-00 W.T. Ellis Alaska Earth Sciences
Reporter 05-DEC-00 Hawley, C.C. Hawley Resource Group
Reporter 05-DEC-00 W.J. Nokleberg U.S. Geological Survey