|Quadrangle map, 1:250,000-scale||DE|
|Quadrangle map, 1:63,360-scale||D-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||These occurrences are at the head of Gold Harbor where the Bureau of Mines took numerous samples along about a mile of shoreline (Maas and others, 1991). The coordinates are approximately at the center of the sample area, in the NW1/4 section 23, T. 80 S., R. 82 E. The location is accurate.|
Geologic descriptionA small Cretaceous granitic pluton intrudes pre-Ordovician marble at the head of Gold Harbor. Mass and others (1991) extensively sampled four contact zones of the granite. Two of the contact zones have sulfides. Samples from one zone that contained tennantite assayed up to 4.39 ounces of silver per ton and 0.142 part per million (ppm) gold. The other mineralized zone is hornfels that contains pyrite, molybdenite, and chalcopyrite across a width of 10 to 15 feet. Samples of this zone contained up 431 ppm molybdenum and 0.4 percent copper.
|Geologic map unit||(-133.016959700301, 54.9249517187942)|
|Mineral deposit model||Sulfides in contact zone of granite.|
|Age of mineralization||Related to the contact zone of Cretaceous granite.|
|Alteration of deposit||Contact metamorphism of marble adjacent to Cretaceous granite.|
|Workings or exploration||None; no indication of work beyond sampling along the shoreline by government geologists.|
|Indication of production||None|
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.
|Reporters||D.J. Grybeck (Applied Geology)|
|Last report date||9/1/2003|