Uneven, Uneven, Conchoidal, Uneven, Gems, Sixth Edition (2006)
UnevenWalter Schumann, Gemstones of the world (2001) More from other references, UnevenWalter Schumann, Gemstones of the world (2001) More from other references, Uneven
Perfect on {001}, good on {010}
{110} Perfect, {110} Perfect, {110} Perfect
(Na,Ca)Al1-2Si3-2O8
(Zn,Fe)SMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references