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
Subconchoidal, Conchoidal, Brittle
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
1.6 Cleavage
Fair on {100}, poor on {001} and {010}
Vitreous, pearly on cleavage
1.7 Mohs Hardness
1.8 Chemical Composition
Mg2Al4Si5O18
(Fe2+ ,Mg,Mn2+ ) 3(PO 4) 2 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references