Gemstones of the world (2001)
Uneven, Conchoidal, Uneven, Irregular, Conchoidal, Management Team (2012)
Microcline: KAlSi3O8 Oligoclase: (Na,Ca)Al1-2Si3-2O8
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.