Handbook of mineralogy (2001), Difficult, Fibrous
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Uneven
Ca 6Si 6O 17(OH) 2Michael OâDonoghue , Gems, Sixth Edition (2006)
Fe3+ PO 4 · 2H 2OAnthony et al , Handbook of Mineralogy (2001)