Subconchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Conchoidal
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001)
LiAlSi 4O 10Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Ca 5(PO 4) 3FAnthony et al , Handbook of mineralogy (2001)