Uneven
ConchoidalAnthony et al, Handbook of mineralogy (2001), ConchoidalAnthony et al, Handbook of mineralogy (2001), Brittle, Conchoidal
K(Al,Cr) 3Si 3O 10(OH) 2Gemdat.org , Management Team (2012)
CaBe 2(PO 4) 2Michael OâDonoghue , Gems, Sixth Edition (2006)