ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), Brittle
SiO 2 + H 2OUlrich Henn and Claudio C.
MgCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references