Tenacity
-
Brittle
Solubility
-
-
Durability
-
-
Specific Gravity
3.1-3.23.21-3.38
1
7.18
👆🏻
Fracture
-
Irregular/uneven, Uneven
Cleavage
Vitreous, pearly on cleavage
Perfect on {001}
Mohs Hardness
3-46-7
2
10
👆🏻
Chemical Composition
(Fe2+ ,Mg,Mn2+ ) 3(PO 4) 2 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Ca 2Al 3(SiO 4) 3(OH)Walter Schumann , Gemstones of the world (2001) More from other references