Editing Feldspar (section)

===Barium feldspars===
Barium feldspars form as the result of the substitution of barium for potassium in the mineral structure. Barium feldspars are sometimes classified as a separate group of feldspars,<ref name="DeerHowieZussman2001"/> and sometimes they are classified as a sub-group of alkali feldspars.<ref name="MindatGroup">{{cite web | url=https://www.mindat.org/min-1624.html | title=Feldspar Group | publisher=mindat.org | accessdate=4 July 2021}}</ref>

The barium feldspars are monoclinic and include the following:
* [[celsian]] {{chem2|BaAl2Si2O8}}<ref>[http://www.mindat.org/min-32214.html Celsian–orthoclase series on Mindat.org].</ref>
* [[hyalophane]] {{chem2|(K,Ba)(Al,Si)4O8}}<ref>[http://www.mindat.org/min-8731.html Celsian–hyalophane series on Mindat.org].</ref>