Uneven, Conchoidal, ConchoidalArthur Thomas, Gemstones (2009)
Uneven, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Brittle, Metallic
Perfect {010} imperfect {100}
{0001} Imperfect, {1120} Imperfect
Ca2Al3(SiO4)3(OH)
KCa 2AlBe 2Si 12O 30 · 0.5H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references