nouna white, creamy yellow, red, or green mineral of the feldspar group, found in igneous, sedimentary, and metamorphic rocks: used in the manufacture of glass and ceramics. Composition: potassium aluminium silicate. Formula: KAlSi3O8. Crystal structure: triclinic
Word origin
C19: from German
Mikroklin, from
mikro- micro- + Greek
klinein to lean; so called because its cleavage plane is slightly different from 90°