Afwillite

General Information: Chemical Formula:Ca3Si2O4(OH)6 Composition:(Molecular Weight = 342.45 gm)Calcium 35.11 % CaSilicon 16.40 % SiHydrogen 1.77 % H Oxygen 46.72 % O  Empirical Formula: Ca3(Si2O4)(OH)6 Environment:Alteration product of spurrite. Locality:TL: Dutoitspan diamond mine at Kimberly, South Africa.Physical Properties: Cleavage:[001] Perfect, [???] Distinct Color:colorless or white. Density:2.62 Diaphaniety:Transparent to Subtransparent to translucent Habits:Massive - Uniformly indistinguishable crystals forming large masses., Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline)., Hardness:3 - Calcite Luster:Vitreous (Glassy) Streak:whiteMore details...