New Mexico Geological Society Annual Spring Meeting — Abstracts

Lithium. The name appears on our batteries and electronic devices. But what is Lithium? What makes this element work in our power supplies? Where does it come from and how do we get it? And, what about Lithium in New Mexico?

Lithium is a critical mineral used in lubricants, metal alloys, medical products, ceramics and glass, and most commonly, batteries. As we move to alternative energy and electric vehicles, the uses and demand for Lithium is increasing. Global production of Lithium rose over 11-fold from 1995 to 2021 growing from 9.5 kTonnes to 106 kTonnes annually.

Lithium is the lightest of all metals. It has a single electron in its valence shell which is readily given up to form a cation in reactions. This makes it a very reactive metal that must be stored away from air and water but gives Lithium its good thermal and electrical conductivity—key properties for use in batteries.

Economically-viable deposits of Lithium occur in three major categories: in pegmatites typically as the minerals spodumene and lepidolite (LiAlSi₂O₆ and K(Li,Al)₃(Si,Al)₄O₁₀(F,OH)₂); in volcanic clays as hectorite, montimorillonite and bentonite (Na_0.33(MgLi)₃Si₄O₁₀(F,OH)₂, (Na,Ca)_0.33(Al,Mg)₂Si₄O₁₀(OH)₂•nH₂O); and from brine and geothermal deposits which includes solar evaporates, playa lakes, and extracted subsurface brines from petroleum and geothermal production.

Although currently not in production in New Mexico, we accounted for about 10% of US Lithium output from 1920 to 1950. Most of that production came from the Harding Pegmatite Mine in the Picuris District, Taos County. Since 1950 no Lithium has been mined in New Mexico but work is currently underway exploring sources of Lithium in the state that could be economically produced. There are several known Lithium sources from pegmatites in north-central New Mexico but these are not likely to be developed in the near future. Volcanic clays occur across many parts of the state and a few have potential for development in the near-term. The Popotosa Formation of the Rio Grande Rift has notable amounts of Lithium in its tuff layers. Diatomite and zeolite deposits in the Gila Conglomerate in the Buckhorn area near Silver City offer another potential source of Lithium. Brine and hydrothermal/geothermal deposits offer some of the best sources of Lithium and other minerals in the short term. The Lordsburg, Tularosa, and Estancia basins all have measurable amounts of Lithium that make them potential development areas.

At the Bureau of Geology we have several projects exploring critical minerals in the state, including Lithium. Sampling and analyses are being conducted on porphyry deposits, carbonatites, mine wastes, and coal-related materials looking for viable sources of critical industrial minerals such as Lithium. A recent grant from the State of New Mexico to research our state’s geothermal resources may also include examining the potential to co-produce Lithium and other minerals from geothermal fluids in a manner similar to current work being done at the Salton Sea in southeast California.