Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Brittle, Conchoidal
UnevenArthur Thomas, Gemstones (2009), UnevenArthur Thomas, Gemstones (2009), Conchoidal, Brittle
Perfect on {001}, good on {210}, poor on {010}
Perfect on {110} at 56° and 124°; partings on {010} and {100}
SrSO 4Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Ca 2Mg 5Si 8O 22(OH) 2Ulrich Henn and Claudio C.