Lithium ( Li ) does not occur in a free state in nature ( природа ) , nor are its compounds very abundant as minerals. The characteristic mode of occurrence of lithium minerals is in pegmatites ( пегматиты ) , where there has been a concentration of this somewhat rare element during the latter stages of consolidation of granite magma ( гранитная магма ) . The most common lithium minerals are:
silicates ( силикаты ) lithium-bearing micas (lepidolite ( лепидолит ) K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 , zinnwaldite KLiFeAl(AlSi3)O10(OH,F)2 )
petalite, LiAlSi4Ol0
spodumene, LiAISi2O6
phosphate ( фосфат ) amblygonite, Li (F, OH) AlPO4
Spodumene, petalite, amblygonite and lepidolite are sources of lithium salts. Production figures are not always available, but in 1985 Zimbabwe produced 30 000 t (of Li2CO3 equivalents), with the USA (15 000 t) and China also being important producers. In 1990, Chile will start production with a capacity of 30 000 t per annum, and initial production estimated at 10 000 t per annum. The annual world consumption of lithium metal and equivalents in 1985 was estimated at 59 700 million lb (5091 t pure Li metal), with USSR production unknown but estimated at around 4000 t per annum. Lithium carbonate is produced in increasing amounts from brines ( рассолы ) in the western USA. Lithium salts are used in glass ( стекло ) , batteries, television tubes, ceramics ( керамика ) , molten carbonate fuel cells and in aluminium lithium alloys ( сплавы ) for the aerospace industry.
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