Aluminium is a much used metal, but it cannot be just dug out of the ground. Usually it is mined in the form of aluminium hydroxide (alumina). A smelter heats the alumina until it is molten, mixes it with molten cryolite - a fluoride salt - and then performs electrolysis to yield elemental aluminium. When the International Aluminium Consortium of Western Australia proposed a smelter for Kemerton, WA, they commissioned a study to check on the environmental effects, as scientists in other locations had reported damaging effects on the plant life around smelters.