Uneven, Uneven, ConchoidalGemdat.org, Management Team (2012)
Uneven, Uneven, Gems, Sixth Edition (2006), Uneven, Conchoidal
Mg 3Al 2(SiO 4) 3 -Mn2+3Al 2(SiO 4) 3Gemdat.org , Management Team (2012)
NaAlSi 3O 8Michael OâDonoghue , Gems, Sixth Edition (2006)