ConchoidalWalter Schumann, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Splintery
Conchoidal, Conchoidal, Gemstones (2009), Uneven
{100} Distinct, {110} Distinct
Perfect on { 2 01} fair on {010}
Na 4Al 3Si 9O 24Cl to Ca 4Al 6Si 6O 24(CO 3,SO 4)Walter Schumann , Gemstones of the world (2001) More from other references
Cu2CO3(OH)2