Vyuntspakhkite-(Y)

General Information: Chemical Formula:(Y,Yb,Er)4Al2AlSi5O18(OH)5 Composition:(Molecular Weight = 1,082.32 gm)Yttrium 19.71 % Y Erbium 6.18 % ErYtterbium 19.19 % YbAluminum 7.48 % AlSilicon 12.97 % SiHydrogen 0.47 % H Oxygen 34.00 % O  Empirical Formula: Y2.4Yb1.2Er0.4Al3Si5O18(OH)5 IMA Status:Approved IMA 1987Physical Properties: Cleavage:None Color:colorless or orange. Density:4.02 Diaphaniety:Transparent Hardness:6-7 - Orthoclase-Quartz Luster:Adamantine Streak:whiteMore details...