Uneven, Uneven, Gems, Sixth Edition (2006)
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Uneven
Al 2O 3Michael OâDonoghue , Gems, Sixth Edition (2006)
Fe3+ PO 4 · 2H 2OAnthony et al , Handbook of Mineralogy (2001)