UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Uneven
Uneven, Uneven, Gemstones of the world (2001) More from other references
Mg 6Cr 2(CO 3)(OH) 16 · 4H 2OMichael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Ca 10Mg 2Al 4(SiO 4) 5(Si 2O 7) 2(OH) 4Ulrich Henn and Claudio C.