(Min.) A rare mineral, occurring crystallized and in cleavable masses, usually white, or nearly so, in color. It is a silicate of aluminia and lithia.
petalite
petalite
[′ped·əl‚īt] (mineralogy) LiAlSi4O10 A white, gray, or colorless monoclinic mineral composed of silicate of lithium and aluminum, occurring in foliated masses or as crystals.