Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
2.825.85-6.15
1
7.18
👆🏻
Fracture
-
Conchoidal
Cleavage
Perfect in one direction, indistinct in one direction
Fair in four directions forming octahedrons
Mohs Hardness
63.5-4
2
10
👆🏻
Chemical Composition
K2Na(Ca,Mn)2Ti[O|Si7O18(OH)]
Cu 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references