Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.33-2.373.76-3.77
1
7.18
👆🏻
Fracture
Uneven
-
Cleavage
Perfect on {001}, imperfect on {110}
{110} Perfect, {110} Perfect
Mohs Hardness
4.5-55-6
2
10
👆🏻
Chemical Composition
(K,Na)Ca4Si8O20(F,OH)•8(H2O)
(Fe,Mn) 7Si 7O 21Ulrich Henn and Claudio C.