Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
3.7-3.83.32-3.43
1
7.18
👆🏻
Fracture
Subconchoidal, Conchoidal
Conchoidal
Cleavage
Distinct on {010}
Poor on {110} and {100} very poor on {001}
Mohs Hardness
7-7.56-7
2
10
👆🏻
Chemical Composition
(Fe,Mg,Zn) 2Al 9(Si,Al) 4O 22(OH) 2Ulrich Henn and Claudio C.
Ca10(Mg,Fe)2Al4(SiO4)5(Si2O7)2(OH)4