Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Uneven
Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
Mn 3B 7O 13ClMichael OâDonoghue , Gems, Sixth Edition (2006)
Al 2SiO 5Arthur Thomas , Gemstones (2009)