Studies of minerals from Hall's Valley, Park County, Colorado – Chemistry of cupropavonites (5,5) ( 5,5P) and (4,6) ( 4,6P): crystal structure of natural pavonite and crystal structure of orthorhombic berryite

The crystal structures of two inter-grown variants of the mineral cupropavonite, ideal composition AgCu2PbBi5S10, were previously reported in a single crystal extracted from type specimen USNM92902 from Hall's Valley, Park County, Colorado. Here we report the chemistry of the separate intergrowths from a similar crystal from the same specimen, determined by electron-probe (EMP) analysis of the two. In addition, the crystal structure of naturally formed pavonite, Ag0.67Cu0.33Bi2.66Pb0.33S5, and preliminary verification of the crystal structure of an orthorhombic modification of berryite, ideally Cu3Ag2Pb3Bi7S16, are presented and discussed.