ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Ca 3Fe 2(SiO 4) 3Arthur Thomas , Gemstones (2009)
SiO 2 + H 2OUlrich Henn and Claudio C.