Lithium: Extraction

Desert brine ponds versus hard-rock mines

Lithium comes from two main sources. In the salt flats of Chile, Argentina and Bolivia, brine is pumped into kilometre-scale evaporation ponds; SQM first pumped Atacama brine for potash, with lithium as a by-product (Conway, pdf p. 287). In Australia, Zimbabwe, Brazil and China, hard-rock spodumene is blasted, crushed and concentrated to about 6% lithium oxide. Brine quality varies: Uyuni has under half Atacama's lithium per litre and over three times the magnesium (Conway, pdf p. 293). Hard-rock lithium carries much higher emissions and water use than Chilean brine. Clays and geothermal brines are under development in the US.

Lithium reaches the market by two main routes. In the 'lithium triangle' of Chile, Argentina and Bolivia, salty brine under salt flats is pumped into ponds and the sun concentrates it over a year or more before a chemical plant turns it into carbonate. In Australia, Zimbabwe, Brazil, Mali and Canada, hard-rock spodumene is mined and concentrated to about 6% lithium oxide, then shipped, mostly to China, for conversion into carbonate or hydroxide. China also mines lepidolite and its own brines at higher cost. New methods, direct lithium extraction from brine and clays, are being built out, and recycling is starting.

Methods compared

How each method works

Pegmatite is mined by open pit, crushed and upgraded by dense-media separation and flotation to SC6 concentrate. Concentrate is shipped to converters, mostly in China, which roast it, leach with sulphuric acid and precipitate carbonate or hydroxide.

Fast to build and ramp, but costlier, more energy- and emission-intensive, and dependent on Chinese conversion.

Brine is pumped from beneath salt flats into a series of ponds where solar evaporation over many months precipitates halite and potash, concentrating lithium. The concentrate is trucked to a plant that removes magnesium and boron and precipitates lithium carbonate.

Lowest cost and lower emissions, but slow to expand, water-use disputes with communities, and royalty and state-partnership terms in Chile.

Lithium-bearing mica (lepidolite) in Jiangxi is mined and treated with sulphate or chloride roasting and leaching. Grades are low, so large volumes of tailings result, and the route is the marginal, highest-cost supply that switches off first in price slumps.

Domestic Chinese supply that responds fast to price, but high cost and environmental scrutiny.

Adsorbents, ion-exchange resins or membranes pull lithium straight from brine, which is then reinjected, cutting the pond stage from months to hours. Rio Tinto's Fenix operation in Argentina uses a selective adsorption process; clay projects in Nevada and Mexico use acid leaching.

Higher recovery and smaller footprint, but each brine needs its own chemistry and capex is high; S&P Global (Sept 2025) flags technology and quality risks in the next project wave.

By-product supply

Lithium is mostly a main product, but the brine route ties it to potash: SQM began pumping Atacama brine for potash with lithium as a by-product (Conway, Material World), and potash, iodine and boron still share the same ponds. Hard-rock lithium is mined for its own sake, so supply responds to price, though with a lag of several years for new mines and converters.

Share produced as a by-product

Who does it: global

Who does it: India

India mines no lithium and has no commercial conversion plant, so all lithium arrives inside imported cells or as small chemical imports (India took 0.9% of world lithium hydroxide imports by value in 2024, UN Comtrade). GSI reported 5.9 Mt of inferred lithium ore resources at Salal-Haimana in Reasi, Jammu and Kashmir, in 2023, but two auction attempts drew no bids (Tribune, March 2025) and GSI's G2 exploration was due by January 2026. Under the ACC PLI scheme 40 GWh of the 50 GWh target had been awarded by end-2025, but installed capacity was only about 2.5% of that (GreenTechLead 2026).