Unnamed Ag-Au-Cu-Pb-Zn prospect (1), Dolomi Mountain, Prince of Wales Island, Ketchikan Mining District, Prince of Wales-Hyder Census Area, Alaska, USAi

Regional Level Types
Unnamed Ag-Au-Cu-Pb-Zn prospect (1)	Prospect
Dolomi Mountain	Mountain
Prince of Wales Island	Island
Ketchikan Mining District	Mining District
Prince of Wales-Hyder Census Area	Census Area
Alaska	State
USA	Country

Location: This site includes scattered occurrences of skarn mineralization in the S½ of secs. 19 & 20, T77S, R89E, 3.3 km (2.1 miles) NNE of Dolomi Mountain (coordinates of record), near a small lake informally called "Jesse Lake" in the literature. The coordinates are at about the center of the area of occurrences.

Geology: Sealaska geologists discovered skarn mineralization at this site in 1988 Hedderly-Smith (1999 [Inventory]). The rocks in the area are chlorite schist and greenstone, interbedded with minor limestone, that are part of the Wales Group of Late Proterozoic and Cambrian age (Eberlein and others, 1983; Brew, 1996). The skarn largely consists of quartz, epidote, garnet, and magnetite, with hematite, pyrite, pyrrhotite, chalcopyrite, and sphalerite. Six of Hedderly-Smith's skarn samples contained up to 6,280 parts per million (ppm) copper, 105 ppm lead, 8,630 ppm zinc, 9.2 ppm silver, and 137 parts per billion (ppb) gold. Maas and others (1991) collected a sample of gossan rubble from a borrow pit in the SW1/4 of section 20 that contained 171 ppm copper, 1.4 ppm silver, and 1,686 ppb gold. A sample of pyrite from a boulder collected about 1,500 feet northwest of Jesse Lake contained 102 ppm copper, 2.9 ppm silver, and 6.243 ppb gold. Hale and others (1992) noted stratiform sulfides in four widely spaced borrow pits in the Jesse Lake area; they suggested that they were replacement deposits in carbonate pods in volcaniclastic sedimentary rocks. Three short drill holes in the mineralized outcrops did not encounter additional mineralization.

Workings: Mainly surface examination and sampling of outcrops by government and industry geologists. Three short drill holes in the mineralized outcrops did not encounter additional mineralization.

Age: Younger than the Late Proterozoic or Cambrian host rocks.

Alteration: Skarns in carbonate rocks.

Commodities (Major) - Ag-Au-Cu-Pb-Zn

Development Status: None

Deposit Model: Au-Cu-Zn skarn; stratiform replacement deposits in carbonate pods.

Other Databases

Link to USGS - Alaska:	CR193

Other Regions, Features and Areas containing this locality

References