mi|ca

mi|ca «MY kuh», noun.

a mineral that divides into thin, partly transparent layers; isinglass. Mica is highly resistant to heat and is used in electric fuses and formerly in stove doors and lanterns, where the heat might break glass. Mica is composed essentially of silicate of aluminum, of potassium, or of other metals, occurring in minute, glittering plates or scales in granite and other rocks, or in crystals that separate. »

An outcrop of sandstone and schist with secondary white mica (Science News).

╂[< Latin mīca grain, crumb; perhaps influenced by micāre to shine]