Conchoidal, Splintery
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
KNa 2B 3Si 12O 30Michael OâDonoghue , Gems, Sixth Edition (2006)
(Fe2+ ,Mg,Mn2+ ) 3(PO 4) 2 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references