Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Uneven, Uneven, ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
Ca 3Al 2(SiO 4) 3Arthur Thomas , Gemstones (2009)
SrCO 3Walter Schumann , Gemstones of the world (2001) More from other references