Uneven, Sub-Conchoidal, UnevenWalter 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)
ZnCO 3Michael OâDonoghue , Gems, Sixth Edition (2006) More from other references
Na(Mn2+ ,Ca) 2Si 3O 8(OH)Michael OâDonoghue , Gems, Sixth Edition (2006)