Gems, Conchoidal, Brittle
ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Ca 3Ti4+2(Fe3+2Si)O 12Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
CaBe 2(PO 4) 2Michael OâDonoghue , Gems, Sixth Edition (2006)