ConchoidalGemdat.org, Management Team (2012), ConchoidalGemdat.org, Management Team (2012)
Conchoidal, Uneven, ConchoidalArthur Thomas, Gemstones (2009), Conchoidal, Brittle
(Cu) 3(OH) 2(CO 3) 2 + Cu 2(CO 3)(OH) 2Gemdat.org , Management Team (2012)
Ca 3Al 2(SiO 4) 3Arthur Thomas , Gemstones (2009)