Uneven, Conchoidal, UnevenWalter Schumann, Gemstones of the world (2001)
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Perfect {010}, imperfect {100}
Perfect on {110} at 56° and 124°; partings on {010} and {100}