Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.60-2.642.33-2.37
1
7.18
👆🏻
Fracture
Uneven, Splintery, Conchoidal
Uneven
Cleavage
Absent
Perfect on {001}, imperfect on {110}
Mohs Hardness
6.5-74.5-5
2
10
👆🏻
Chemical Composition
SiO 2Arthur Thomas , Gemstones (2009)
(K,Na)Ca4Si8O20(F,OH)•8(H2O)