Uneven, Subconchoidal, Uneven, Subconchoidal, Splintery, UnevenArthur Thomas, Gemstones (2009)
Splintery, Brittle, Uneven
Al 2SiO 5Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
NaCa 2(Mg 4Al)Si 6Al 2O 22(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006)