Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
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)
1.04 x 10−25 g per 100 ml water (Ksp at 25°C = 2 x 10−32)
Prismatic {10 1 0}, perfect
HgSMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references