Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
{110} Perfect, {010} Indistinct
(Ca,Na)(Mg,Fe,Al,Ti)(Si,Al) 2O 6Anthony et al , Handbook of mineralogy (2001)
Subconchoidal, Conchoidal
(Fe,Mg,Zn) 2Al 9(Si,Al) 4O 22(OH) 2Ulrich Henn and Claudio C.