Low-grade, molybdenum porphyry occurs in a complex contact region of the Pennsylvanian- to Permian-age Ahtell pluton; mostly in the Border phase and in the overlying volcanic rocks of the Pennsylvanian- to Permian-age Slana Spur Formation. Argillic and sericite alteration; argillic alteration is probably accentuated by supergene acid solutions formed by oxidation of pyrite. Discovered in 1957, but no work was done until 1968; drilling in 1968 and 1969 showed that most of the deposit is very lowgrade, but two shallow holes intercepted rich mineralization.
Study area name
U.S. Geological Survey (2014a); Richter (1966)
U.S. Geological Survey National Mineral Resource Assessment Team (2002)