Talking about a mine in the lithium mining site, we first imagine a cave-like tunnel in the earth where workers excavate rock and rare earth ores with pickaxes and heavy diggers. But in mining lithium a slightly different process is preffered.
Lithium has historically been produced from two sources: brines and hard rock mining. Producing lithium from brines remains the most efficient and cost effective process. The cost-effectiveness of brine operations forced even large producers in China and Russia to develop their own brine sources or buy raw materials from brine producers.
These brines contain lithium derived mainly from the leaching of volcanic rocks and vary greatly in lithium content, largely as a result of the extent to which they have been subject to solar evaporation. They range from highly concentrated lithium deposits in the high altitude salars of Chile, Argentina, Bolivia, Tibet and China where lithium concentrations can be very high; to mid-level brines like Silver Peak, Nevada and Searles Lake, California (a former location of lithium production); to lower concentration brines like the Great Salt Lake, Utah. The lower concentration brines have modest evaporation rates and dilution is constant due to a large volume of fresh water inflow and small lithium concentrations varying between 30 to 60 ppm.
The effectiveness of producing lithium carbonate from salt brines is so favourable that most hard rock mining operations have been priced out of the market. Lithium brines are currently the only lithium source that can support mining without significant other credits from tantalum, niobium, tin etc.
Once the lithium is recovered by-products include saleable compounds such as potash or boron and the chemicals used can be recycled. Lithium recovery from brines may lead to a significant carbon footprint reduction because of a nearly zero-waste mining method.
It may seem like lithium is a rare metal but that is not entirely true. Lithium is found in many places on our planet, including in our oceans. However, the extraction and processing takes scientific expertise, clever engineering and investments to produce industry-grade lithium.