Tenacity
Solubility
Durability
Specific Gravity
Fracture
Cleavage
Mohs Hardness
Chemical Composition
(Mg,Fe2+ ) 5Al(Si 3Al)O 10(OH) 8Anthony et al , Handbook of mineralogy (2001)
Perfect on {110} at 56° and 124°; partings on {010} and {100}
Ca 2Mg 5Si 8O 22(OH) 2Ulrich Henn and Claudio C.