A soft, silvery-white metallic element of the alkali group, the lightest of all metals. Symbol, Li. Does not occur free in nature; is found combined in small amounts in nearly all igneous rocks and in the waters of many mineral springs. Lepidolite, spodumene, petalite, and amblygonite are the more important minerals containing it. The metal is corrosive and requires special handling. Used as an alloying agent, in the synthesis of organic compounds, and for nuclear applications.