Preliminary report on certain metals of potential economic interest in thin vanadium-rich zones in the Meade Park member of the Phosphoria Formation in western Wyoming and eastern Idaho

Electron microprobe, optical and chemical studies of fresh and weathered rocks permit preliminary conclusions concerning the concentration and mineralogical residence of certain elements of potential economic significance in thin, vanadium-rich zones in the Meade Peak Member of the Phosphoria Formation in western Wyoming and eastern Idaho. Elements of particular interest are V, Cr, Zn, Cd, Ag, Se, S, Ti, and Mo. Their principal mineralogical residence in fresh or unweathered rock has been established as follows: V is in, or associated with, organic material and minor amounts of V are in Ti-Fe oxysulfide and an unidentified Fe sulfide; Cr is in a 10 A mica. Zn and Cd are in sphalerite; Se is in pyrite; S is in pyrite, sphalerite and organic material; Ti is in TiO₂ and Ti₂ Fe(SO₃ )₂ and Mo is in powellite. The principal minerals in fresh rocks are quartz, K-feldspar, albite, illite, calcite, and dolomite. Weathering or leaching by ground water removes pyrite, calcite, and dolomite. The leached rock sequences currently mined for phosphate may be amenable to extraction of the metals associated with the organic material.