ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Conchoidal, Brittle
Gemstones (2009), UnevenArthur Thomas, Gemstones (2009)
Al 2(Cl 2O 12) · 18H 2OUlrich Henn and Claudio C.
Al 2SiO 5Arthur Thomas , Gemstones (2009)