Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
{010} Good, {100} Distinct
(Mn2+ ,Fe2+ ,Mg,Ca) 2(PO 4)(F,OH)Michael OâDonoghue , Gems, Sixth Edition (2006)
Uneven, Irregular, Conchoidal
Ca 3Al 2(SiO 4) 3-x(OH) 4x (x=0.2 to 1.5)Anthony et al , Handbook of mineralogy (2001)