Lithium-rich brines in the Central Andean salars of Argentina, Bolivia, and Chile

Abstract

The Central Andes of South America are characterized by a succession of ~N-S trending ranges and closed basins occupied by numerous ‘saline lakes’, ‘salt crusts’, and ‘salars’. The term ’salar’ describes a continental saline deposit composed mainly of a salt crust, brine with dissolved elements of potential economic interest, and a clastic fraction of sedimentary and/or volcanic origin, formed by the evaporation of groundwater in hydrographically closed arid basins. The discovery of lithium-rich brines in the Salar de Atacama (northern Chile) in 1969 initiated the identification of one of the world’s major lithium-rich brine regions. Today, the Central Andes account for a significant portion of the world’s lithium production; for example, in 2025, Chile and Argentina produced 27% of the estimated world’s total of 290,000 tons of lithium. The region became a major producer due to the large size of its deposits and the high quality of its lithium-rich brines. In addition to lithium, the brines contain potassium, boron, and magnesium. Out of the 130 salars known in the Central Andes, this contribution focuses on 43 evaluated deposits with lithium-rich brines reported to date. Reports, evaluations, and exploration surveys provide an updated perspective on the state of knowledge regarding lithium-rich brines in the Central Andes. Recent developments are promising: the identified lithium reserves and resources, together with favorable exploration prospects, position this region as a significant contributor to the global lithium industry.