Wroewolfeite, a New Copper Sulphate Hydroxide Hydrate

Pete J. Dunn and Roland C. Rouse
Department of Mineral Sciences, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560
with chemical analysis by Joseph A. Nelen

Summary: Wroewolfeite is a new mineral from the Loudville lead mine in Loudville, Massachusetts, U.S.A. The mineral occurs as blue, monoclinic crystals, twinned on {001}, very similar in appearance to posnjakite and langite. It is formed as small isolated pinacoidal crystals (up to 1·0 ram) implanted on covelline and chalcosine. There are three cleavages of equal facility of production. The cell dimensions are a 6·058 Å, b 5·654 Å, c 14·360 Å, β 93° 28′, space group Pc or P2/c. The strongest diffraction lines (in Å) are 7·152 (100), 3·581 (70), 2·628 (35), 2·004 (30), 2·431 (20), 2·379 (20), 2·278 (20). Electron microprobe analysis gives CuO 64·22 %, SO3 16·48 %, water by difference 19·30 %. Empirical cell contents are Cu7·88(SO4)2·00(OH)11·76. (H2O)4·22 or Cu4(SO4)(OH6.2H2O with Z = 2. Wroewolfeite is strongly pleochroic with α light blue, β deep greenish blue, and γ medium greenish blue. Absorption β > γα. The mineral is biaxial with α 1·637, β 1·682, and γ 1·694, 2Vα = 53°. The name is for C. Wroe Wolfe, American crystallographer, educator, and philosopher.

Mineralogical Magazine; March 1975 v. 40; no. 309; p. 1-5; DOI: 10.1180/minmag.1975.040.309.01
© 1975, The Mineralogical Society
Mineralogical Society (www.minersoc.org)