Conchoidal, Uneven, Conchoidal, Brittle, ConchoidalArthur Thomas, Gemstones (2009)
UnevenWalter Schumann, Gemstones of the world (2001) More from other references, UnevenWalter Schumann, Gemstones of the world (2001) More from other references, Uneven
Ca 3Fe 2(SiO 4) 3Arthur Thomas , Gemstones (2009)
(Zn,Fe)SMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references