Nealite

General Information: Chemical Formula:Pb4Fe++(As+++++O4)2Cl4 Composition:(Molecular Weight = 1,304.30 gm)Iron 4.28 % FeArsenic 11.49 % AsLead 63.54 % PbChlorine 10.87 % ClOxygen 9.81 % O  Empirical Formula: Pb4Fe2+(AsO4)2Cl4 Environment:Lead slags. Locality:Laurion, Attica, Greece. Name Origin:Named of Leo Neal Yedlin (1908-1997), micromount mineral collector of New Haven, Conneticut, USA.Physical Properties: Cleavage:None Color:yellow or light orange. Density:5.88 Diaphaniety:Translucent Habits:Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Bladed - Aggregates of thin lath-like crystals (e.g. kyanite)., Hardness:4 - Fluorite Luminescence:Non-fluorescent. Luster:Adamantine Streak:light orangeMore details...

General Information: Chemical Formula:Pb4Fe++(As+++O3)2Cl4·2(H2O) Composition:(Molecular Weight = 1,308.33 gm)Iron 4.27 % FeArsenic 11.45 % AsHydrogen 0.31 % H Lead 63.35 % PbChlorine 10.84 % ClOxygen 9.78 % O  Empirical Formula: Pb4Fe2+(AsO3)2Cl4·2(H2O) Environment:Weathered lead slag. Locality:Laurion, Greece. Name Origin:Named for Neal Yedlin (1908-1977), U. S. Mineralogist, who discovered the mineral.Physical Properties: Cleavage:None Color:bright orange. Density:5.89 Habits:Microscopic Crystals - Crystals visible only with microscopes., Bladed - Aggregates of thin lath-like crystals (e.g. kyanite)., Luster:Adamantine Streak:pale orangeMore details...