ConchoidalWalter Schumann, ConchoidalWalter Schumann, Gemstones of the world (2001) More from other references, Brittle, Metallic
UnevenAnthony et al, Handbook of mineralogy (2001), UnevenAnthony et al, Handbook of mineralogy (2001), Uneven
Perfect on {010}, good on {100}
{010} Perfect, {001} Distinct
Be 2BO 3(OH)Ulrich Henn and Claudio C.
Fe3+ PO 4 · 2H 2OAnthony et al , Handbook of Mineralogy (2001)