Penikisite

General Information: Chemical Formula:BaMg2Al2(PO4)3(OH)3 Composition:(Molecular Weight = 583.72 gm)Barium 23.53 % BaMagnesium 7.29 % MgAluminum 9.24 % AlIron 2.39 % FePhosphorus 15.92 % P Hydrogen 0.52 % H Oxygen 41.11 % O  Empirical Formula: BaMg1.75Fe2+0.25Al2(PO4)3(OH)3 Environment:Forms a series with kulanite (Fe-end member). IMA Status:Approved IMA 1977 Locality:Rapid Creek (Cross Cut Creek), Big fish River, Yukon Territory, Canada. Name Origin:Named for Gunar Penikis (1936-1979), who discovered the locality.Physical Properties: Cleavage:[010] Good, [110] Good Color:blue or green. Density:3.79 Diaphaniety:Transparent to Translucent Habits:Platy - Sheet forms (e.g. micas)., Rosette - Bundled tabular aggregates resembling rose flower petals., Hardness:4 - Fluorite Luminescence:Non-fluorescent. Luster:Vitreous (Glassy) Streak:whiteMore details...

Ba(Mg,Fe)2Al2(PO4)3(OH)3