Makarochkinite

General Information: Chemical Formula:(Ca,Na)2(Fe++,Fe+++,Ti,Mg,Mn)6(Si,Be,Al)6O20 Composition:(Molecular Weight = 837.17 gm)Sodium 1.37 % NaCalcium 7.18 % CaMagnesium 1.45 % MgTitanium 5.15 % TiManganese 0.66 % MnBeryllium 1.94 % BeAluminum 1.93 % AlIron 30.02 % FeSilicon 12.08 % SiOxygen 38.22 % O  Empirical Formula: Ca1.5Na0.5Fe2+3Fe3+1.5Ti0.9Mg0.5Mn2+0.1Si3.6Be1.8Al0.6O IMA (SO4)2(OH)2·7(H2O) Composition:(Molecular Weight = 463.94 gm)Iron 24.07 % FeHydrogen 3.48 % H Sulfur 13.82 % S Oxygen 58.63 % O  Empirical Formula: Fe3+2(SO4)2(OH)2·7(H2O)Physical Properties: Cleavage:[???] Perfect, [???] Imperfect Color:brown, orange brown, or reddish brown. Density:2.2 Diaphaniety:Transparent to Translucent Hardness:3 - Calcite Luminescence:Non-fluorescent. Luster:Vitreous (Glassy) Streak:orangeMore details...

(Ca,Na)2(Fe,Ti,Mg)6(Si,Al,Be)6O20