Unknown (east of Abraham Bay)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Fe
Other commodities Cu; Pb
Ore minerals chalcopyrite; galena; pyrite

Geographic location

Quadrangle map, 1:250,000-scale AT
Quadrangle map, 1:63,360-scale C-4
Latitude 52.85
Longitude 172.82
Nearby scientific data Find additional scientific data near this location
Location and accuracy This site represents numerous occurrences east of Abraham Bay on Attu Island. Its specific location is not known. The map site is plotted at an elevation of about 1,200 feet and about 3 miles east of Abraham bay, and is probably accurate to within 3 miles.

Geologic setting

Geologic description

On Attu Island partly oxidized zones of pyrite occur in many rock types, including basalt and andesite flows and pyroclastics (Gates and others, 1971). The zones range in size from small isolated pods a few feet in diameter to broad areas 2 to 3 miles long and one mile wide. Many elongate zones or small, isolated patches trend or are aligned east-west.
The pyritic zones are associated with swarms of hornblende-bearing dikes and are rich in pyrite, calcite, albite, and zeolites. Base metals are rare and only a few crystals of chalcopyrite and galena have been noted.
Geologic map unit (-172.822431229512, 52.8488009508188)
Age of mineralization Tertiary or younger.
Alteration of deposit Albite, calcite, iron-oxides, and zeolites (descriptions are not clear and some of these may represent gangue minerals).

Production and reserves

Indication of production None

Additional comments

Site is located in Alaska Maritime Natural Wildlife Refuge.

References

MRDS Number 10307226
Reporters S.H. Pilcher (Anchorage)
Last report date 1/22/2000