ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009)
Ca 3Al 2(SiO 4) 3Arthur Thomas , Gemstones (2009)
Ca 5(F,Cl)(PO 4) 3Arthur Thomas , Gemstones (2009)