Uneven, Uneven, ConchoidalWalter Schumann, Gemstones of the world (2001)
Conchoidal, Conchoidal, Gemstones of the world (2001)
Na(Li 1.5Al 1.5)Al 6(Si 6O 18)(BO 3) 3(OH) 3(OH)Gemdat.org , Management Team (2012) Formula given for elbaite.
SiO 2 · nH 2OWalter Schumann , Gemstones of the world (2001) More from other references