Tenacity
Brittle
-
Solubility
-
-
Durability
-
-
Specific Gravity
2.454.28-4.42
1
7.18
👆🏻
Fracture
Conchoidal
Conchoidal
Cleavage
Perfect on {001}, good on {110}
Distinct on [010] and [100] poor on [101]
Mohs Hardness
4-4.55-5.5
2
10
👆🏻
Chemical Composition
KNa 4Ca 4Si 8O 18(CO 3) 4(OH,F) · H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)
PbCa 3Zn 4(SiO 4) 4Anthony et al , Handbook of mineralogy (2001)