Uneven, Subconchoidal, Uneven, Subconchoidal, Splintery, UnevenArthur Thomas, Gemstones (2009)
Uneven, Uneven, Management Team (2012), Conchoidal, Brittle
Al 2SiO 5Michael OâDonoghue , Gems, Sixth edition (2006) More from other references
Fe 3O 4Ulrich Henn and Claudio C.