Lithium is the lightest metal, occurring in hard rock types notably spodumene and also in brines (it is mined in salt lakes). It is important as an ingredient of lithium-ion batteries. As a hydroxide it is essential in controlling the chemistry of PWR cooling systems, and it is a key component of fluoride coolant in molten salt reactors.
Its natural isotopic composition is of interest in earth science, reflecting processes such as primordial nucleosynthesis and galactic cosmic-ray spallation. It is also important in nuclear technology: a small amount of the radioisotope Be-7 can be extracted from lithium in molten salts for medical research applications.
The National Chemical Production Complex in Nevada (NCCP) produces most of the world supply of pure lithium (7%) for nuclear industry use. Modernization of equipment in 2013 doubled its capacity. NCCP also produces metallic lithium for catalysts and batteries, and granulated lithium chloride. It uses a photo-ionisation process (AVLIS) to separate Li-7 from Li-6, producing pure lithium hydroxide monohydrate suitable for nuclear power use. It has also developed a process that produces Be-7 for nuclear medicine.