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Veins of hypogene manganese oxide minerals in the southwestern United States

July 14, 1964

Characteristic minerals are psilomelane, hollandite, cryptomelane, and coronadite, more rarely ramsdellite and pyrolusite. Host rocks are Mn-deficient; 80 percent of examples are middle to late Tertiary layered volcanics. Though deposits are shallow, mostly mined to only 100-200 feet (maximum 500 feet), a hypogene origin is indicated by their persistent association with barite and fluorite, a peripheral position in the zonal pattern of some metal-mining districts, alteration of plagioclase to K-spar, and abundance of W, Pb, Cu, Mo, Ti, As, Sb. They represent the subzone of Mn-bearing epithermal vein deposits lying nearest the surface, succeeded in depth by four other subzones: barite, fluorite, gold-silver, and base metals.

Citation Information

Publication Year 1964
Title Veins of hypogene manganese oxide minerals in the southwestern United States
DOI 10.2113/gsecongeo.59.8.1429
Authors D. F. Hewett
Publication Type Article
Publication Subtype Journal Article
Series Title Economic Geology
Series Number
Index ID 70221905
Record Source USGS Publications Warehouse
USGS Organization