Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.33-2.372.60-2.64
1
7.18
👆🏻
Fracture
Uneven
Uneven, Splintery, Conchoidal
Cleavage
Perfect on {001}, imperfect on {110}
Absent
Mohs Hardness
4.5-56.5-7
2
10
👆🏻
Chemical Composition
(K,Na)Ca4Si8O20(F,OH)•8(H2O)
SiO 2Arthur Thomas , Gemstones (2009)