Sunday, October 10, 2010

Lithium - What it is and how it is mined

(Reuters) - Here are the key ways of mining lithium, a highly reactive material that is used in batteries for electric and hybrid vehicles. Demand is likely to double over the next decade as more electric vehicles arrive on the road.

Lithium is mined from three sources: lithium brines, spodumene and clay deposits.

Analysts generally agree that cost of production for lithium brines is about half that of spodumene, which is a hard rock. As a result, salt lake exploration has boomed.


Concentration: Not all salt lakes contain lithium, and in order to be cost effective, the concentration should be 600 mg of lithium per liter.

Magnesium: Too much magnesium can also cause problems, a ratio of more than 9:1 magnesium to lithium is considered uneconomical.

Evaporation: With brines, salt water containing lithium is pumped from the ground and into an evaporation pond. Filling the pond takes about a year, then the evaporation process can take anywhere from about eight months to three years.


SQM - Atacama, Chile - over 1000 mg lithium per liter

Rockwood - Atacama, Chile - over 1000 mg lithium per liter

Rockwood - Silver Peak, U.S. - 200 mg lithium per liter

FMC - Hombre Muerto, Argentina - 600 mg lithium per liter

Bolivia - Salar de Uyuni - largest lithium deposit in the world

China - Zabuye, Dongtai, Xitai deposits in Tibet


With spodumene deposits, the rock must be mined, heated up to 1,100 degrees Celsius and then pulverized before the spodumene crystal are processed with acid to produce lithium.