ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Uneven
Be 3Al 2Si 6O 18Ulrich Henn and Claudio C.
Zn 2SiO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references