Lithium is the lightest metal. It has the symbol Li and an atomic number of 3, and comes just after hydrogen and helium in the periodic table. The metal is very reactive in its elemental form and is light enough to float in oil, making it an ideal battery material. Lithium metal never occurs freely in nature, and is usually found in ionic minerals such as petalite, lepidolite and spodumene within pegmatite rocks or in solution in salt brines. Despite being an abundant element in the earth’s crust there are few deposits globally where the lithium concentration is sufficient to make economic extraction a possibility. Due to its importance as a component of batteries used in electric vehicles, lithium is a much sought after critical raw material.