Conchoidal, ConchoidalArthur Thomas, Gemstones (2009), ConchoidalArthur Thomas, Gemstones (2009), Brittle, Conchoidal
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001)
Perfect on [10 1 1] three directions with angle of 74° 55
{100} Perfect, {001} Perfect
CaCO 3Ulrich Henn and Claudio C.
Na(Mn2+ ,Ca) 2Si 3O 8(OH)Michael OâDonoghue , Gems, Sixth Edition (2006)