Uneven, UnevenArthur Thomas, Gemstones (2009)
Subconchoidal, Conchoidal, Brittle, ConchoidalArthur Thomas, Gemstones (2009)
Mg 3Si 4O 10(OH) 2Ulrich Henn and Claudio C.
TiO 2Michael OâDonoghue , Gems, Sixth edition (2006) More from other references