Feldspar an overview | ScienceDirect Topics
Feldspars of importance to ceramics are aluminosilicates of sodium, potassium, and calcium (Jones Berard, 1993) They are used as fluxes to form a glassy phase in bodies, thus promoting vitrification and also serve as a source of alkalis and alumina in glazes. The pure spars are albite (NaAlSi 3 O 8), orthoclase or microcline (KAlSi 3 O 8) and anorthite (CaAl 2 Si 2 O 8).