Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
Subconchoidal, Conchoidal
(Fe,Mg,Zn) 2Al 9(Si,Al) 4O 22(OH) 2Ulrich Henn and Claudio C.
Perfect on {001}, good on {210}, poor on {010}
SrSO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references