1 Physical Properties
1.1 Tenacity
1.2 Solubility
Not Available
Not Available
1.3 Durability
Not Available
Not Available
1.4 Specific Gravity
1.5 Fracture
Gems, Sixth Edition (2006)
Conchoidal, Conchoidal, Brittle
1.6 Cleavage
None
Perfect on {001}, good on {110}
1.7 Mohs Hardness
1.8 Chemical Composition
SiO2 (with a high level of nickel impurities )
KNa 4Ca 4Si 8O 18(CO 3) 4(OH,F) · H 2OMichael OâDonoghue , Gems, Sixth Edition (2006)