Conchoidal, Brittle, Conchoidal, Brittle, Conchoidal, Brittle
Conchoidal, Splintery, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle
(Mg,Fe2+ ) 2(Mg,Fe2+ ) 5Si 8O 22(OH) 2Anthony et al , Handbook of mineralogy (2001)
AlPO4 · 2(H2O)