- An abundant rock-forming mineral typically occurring as colourless or pale-coloured crystals and consisting of aluminosilicates of potassium, sodium, and calcium.More example sentences
- Quartz is associated most commonly with aegirine and potassium feldspar as well as zircon.
- Larger crystals of feldspar and quartz dominate the host rock.
- These granite dikes are composed almost totally of potassium feldspar and quartz.
mid 18th century: alteration of German Feldspat, Feldspath, from Feld 'field' + Spat, Spath 'spar' (see spar3). The form felspar is by mistaken association with German Fels 'rock'.
More definitions of feldsparDefinition of feldspar in:
- The US English dictionary