Occurrence in Alaska, United States with commodities Copper, Silver, Lead

Geologic information

Identification information

Deposit ID 10307260
Record type Site
Current site name Ahua

Geographic coordinates

Geographic coordinates: -161.73365, 67.72945 (WGS84)
Relative position The Ahua prospect is at an elevation of about 1,000 feet near a south-flowing creek that drains the Kilyaktalik Peaks. It is in section 24, T. 27 N., R. 14 W., of the Kateel River Meridian. Schmidt and Allegro (1988), location 47 and field stations 84RB103 and 84JS030.
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Geographic areas

Country State
United States Alaska


Commodity Importance
Copper Primary
Silver Secondary
Lead Secondary

Materials information

Materials Type of material
Marcasite Ore
Pyrite Ore


  • (Local) Sulfide-bearing black shale is stained and bleached.

Mineral occurrence model information

Model code 208
USGS model code 31a
BC deposit profile E14
Deposit model name Sedimentary exhalative Zn-Pb
Mark3 model number 13

Nearby scientific data

(1) -161.73365, 67.72945

Comments on the geologic information

  • Geologic Description = The Ahua occurrence consists of stained and bleached zones in black shale containing lenses of massive, botryoidal pyrite-marcasite. Samples of the sulfides contain as much as 60 ppm As, 2 ppm Ag, 100 ppm Zn, 5 ppm Ag, 700 ppm Ba, 20 ppm Co, 200 ppm Cu, 20% Fe, 30 ppm Mo, 100 ppm Ni and 50 ppm Pb. Pyrite-rich samples contain as much as 200 ppm Cu, 50 ppm Pb, 30 ppm Mo, 100 ppm Ni, 100 ppm Zn, 5 ppm Ag, 60 ppm As, 700 ppm Ba, and 20 ppm Co (Schmidt and Allegro, 1988). The host rocks are Lower Mississippian black shale that are similar to the Kuna Formation (Karl and others, 1985).
  • Age = Early Mississippian.

Economic information

Economic information about the deposit and operations

Development status Occurrence

Comments on exploration

  • Status = Inactive

Mining district

District name Noatak

Comments on the workings information

  • Workings / Exploration = The occurrence has been visited and sampled by the U.S. Geological Survey (Schmidt and Allegro, 1988).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF BM017

Bibliographic references

  • Deposit

    Schmidt, J.M., and Allegro, G.L., 1988, Map showing mineral occurrences and indicators in the Baird Mountains quadrangle, northwestern Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1992, 1 sheet, scale 1:250,000.

  • Deposit

    Zayatz, M.R., Thompson, W.B., Bailey, E.A., Sutley, S.J., Folger, P.F., Karl, S.M., and Schmidt, J.M., 1988, Analytical results and sample locality maps of mineralized and unmineralized rock samples from the Baird Mountains quadrangle, Alaska: U.S. Geological Survey Open-File Report 88-256-A, 159 p., 2 plates, scale 1:250,000.

  • Deposit

    Karl, S.M., Schmidt, J.M., and Folger, P.F., 1985, Selected anomalous rock and sediment samples from central and northwestern Baird Mountains quadrangle, in Bartsch-Winkler, S., ed., The United States Geological Survey in Alaska--Accomplishments during 1984: U.S. Geological Survey Circular 967, p. 8-13.

Comments on the references

  • Primary Reference = Schmidt and Allegro, 1988

General comments

Subject category Comment text
Deposit Model Name = Sedimentary exhalative Zn-Pb (Cox and Singer, 1986; model 31a).

Reporter information

Type Date Name Affiliation Comment
Reporter 29-DEC-99 Williams, Anita U.S. Geological Survey