Tooeleite, a new mineral from the U.S. Mine, Tooele County, Utah

Abstract

AbstractThe new mineral tooeleite occurs with pyrite, arsenopyrite, scorodite, and jarosite at the U.S. Mine, Tooele Country, Utah. Analysis by electron microprobe gave Fe2O3 43.56%, As2O5 38.61%, SO3 7.24%, and H2O by the Penfield method 9.80%. For this analysis, the suggested formula is Fe8-2x3+[(AS1-xSx)O4]6(OH)6.5H20; x is about 0.2.Crystals are orthorhombic, perhaps Pbcm or Pbc21, with a = 6.416, b 19.45, c = 8.941 Å. The strongest diffraction lines are [d in Å, (hkl), (I)] 9.75 (020) (10); 3.208 (200,132) (9); 3.047 (061,220) (5); 4.476 ({002) (4) and 2.680 (240,113) (4). The mineral is optically negative with a small 2V; α = 1.94, β = 2.05, γ = 2.06. Hardness = 3, Dmeas = 4.23, Dcalc = 4.15 g/cm3 for Z = 2.