Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
{110} Perfect, {???} Distinct, {???} Distinct
(Mg,Fe2+ ) 2(Mg,Fe2+ ) 5Si 8O 22(OH) 2Anthony et al , Handbook of mineralogy (2001)
Uneven, Conchoidal, ConchoidalWalter Schumann
Indistinct on {001}; partings on {011} and {111}
FeS 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references