Uneven-Conchoidal, ConchoidalWalter Schumann, Gemstones of the world (2001)
Uneven, UnevenArthur Thomas, Gemstones (2009)
The chief constituent Lapis Lazuli is Lazurite, with the following chemical formula: (Na,Ca)8Al6Si6O24(S,SO)4
KCa 4Si 8O 20(F,OH) · 8H 2OUlrich Henn and Claudio C.