Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Conchoidal, Brittle
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009)
CaB 2(SiO 4) 2Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
K(Ca,Na) 2Si 4O 10(OH,F) · H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references