Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
Uneven, torn surfaces, (e.g. fractured metals)., Uneven, Gemstones (2009), torn surfaces, (e.g. fractured metals).
Mg 2Al 4Si 5O 18Ulrich Henn and Claudio C.
FeO(OH)Arthur Thomas , Gemstones (2009)