Feinglosite

General Information: Chemical Formula:Pb2(Zn,Fe)[(As,S)O4]2·(H2O) Composition:(Molecular Weight = 751.83 gm)Zinc 6.52 % ZnIron 1.86 % FeArsenic 14.95 % AsHydrogen 0.27 % H Lead 55.12 % PbSulfur 2.13 % S Oxygen 19.15 % O  Empirical Formula: Pb2Zn0.75Fe2+0.25(AsO4)1.5(SO4)0.5·(H2O) Environment:The Zn-dominant analogue of arsenbrackebuschite. IMA Status:Approved IMA 1995 (Dana # Added) Locality:Tsumeb mine, Tsumeb, Namibia. Name Origin:Named after Mark D. Feinglos (b. 1948), Professor at the Duke University Medical Center, Durham, North Carolina, U.S.A., who discovered the mineral.Physical Properties: Color:pale olive green. Density:6.52 Diaphaniety:Transparent Hardness:4-5 - Fluorite-Apatite Luster:Adamantine Streak:whiteMore details...