Dolly Varden (ARDF #CR110) Ag, Au

Dolly Varden

Prospect, Undetermined

Commodities and mineralogy

Main commodities	Ag; Au
Ore minerals	azurite; malachite; tetrahedrite
Gangue minerals	quartz

Geographic location

Quadrangle map, 1:250,000-scale	CR
Quadrangle map, 1:63,360-scale	B-3
Latitude	55.34262
Longitude	-132.68865
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	Based on several old but probably reliable references (Brooks, 1902; Wright and Wright, 1908), the Dolly Varden prospect is at an elevation of about 1,100 feet, about 1.7 miles southeast of the head of Twelvemile Arm and about 0.6 mile northwest of the center of section 29, T. 75 S., R. 84 E. Herreid and Rose (1966), probably incorrectly, suggest that the Dolly Varden prospect is about 3 miles to the west at their locality 2 (which is ARDF CR109).

Geologic setting

Geologic description As described by Brooks (1902) and Wright and Wright (1908), the deposit at the Dolly Varden prospect consists of auriferous (quartz?) veins that strike N15E and dip steeply to the SE or are vertical. The veins follow the layering in marble and contain tetrahedrite altered to azurite and malachite. The marble is part of the Wales Group of Cambrian and older age (Eberlein and others, 1983; Brew, 1996). There is no report of workings on these claims. Bufvers (1967) indicates that the quartz stringers occur in an area about 20 feet wide and 30 feet long. A sample taken in 1924 contained $80 a ton in gold and silver. Maas and others (1992, 1995) collected four samples that contained up to 20 parts per billion gold, 7.6 parts per million (ppm) silver, and 1,329 ppm copper.
Geologic map unit	(-132.690301129542, 55.3422673914541)
Mineral deposit model	Polymetallic vein? (Cox and Singer, 1986; model 22c).
Mineral deposit model number	22c?
Age of mineralization	Veins cut marble of Cambrian or older age.

Production and reserves

Workings or exploration	Apparently none.
Indication of production	None

References

MRDS Number	A010038
References Brew, D.A., 1996, Geologic map of the Craig, Dixon Entrance, and parts of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-2319, 53 p., 1 sheet, scale 1:250,000. Brooks, A.H., 1902, Preliminary report on the Ketchikan mining district, Alaska, with an introductory sketch of the geology of southeastern Alaska: U.S. Geological Survey Professional Paper 1, 120 p. Bufvers, John, 1967, History of mines and prospects, Ketchikan district, prior to 1952: Alaska Division of Mines and Minerals Special Report 1, 32 p. Cobb, E. H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Craig quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-869, 262 p. Eberlein, G.D., Churkin, Michael, Jr., Carter, Claire, Berg, H.C., and Ovenshine, A. T., 1983, Geology of the Craig quadrangle, Alaska: U.S. Geological Survey Open-File Report 83-91, 52 p. Herreid, Gordon, and Rose, A.W., 1966, Geology and geochemistry of the Hollis and Twelvemile Creek area, Prince of Wales Island southeastern Alaska: Alaska Division of Mines and Minerals Geologic Report 17, 32 p. 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. Maas, K.M., Still, J.C., and Bittenbender, P.E., 1992, Mineral investigations in the Ketchikan mining district, Alaska, 1991 - Prince of Wales Island and Vicinity: U.S. Bureau of Mines Open-File Report 81-92, 69 p., 1 sheet, scale 1:20. Wedow, Helmuth, White, M. G., and Moxham, R. M., 1952, Interim report on an appraisal of the uranium possibilities of Alaska: U.S. Geological Survey Open-File Report 52-165, 124 p. Wright, F.E., and Wright, C.W., 1908, The Ketchikan and Wrangell mining districts, Alaska: U.S. Geological Survey Bulletin 347, 210 p.
Reporters	D.J. Grybeck (Applied Geology)
Last report date	5/1/2004