Lithium does not occur freely in the nature, but is found combined in small amounts in nearly all igneous rocks, in the waters of the many mineral springs and in seawater. Identified lithium land resources are about 13 milion tons (the sum of the lithium content in ores and brines). Lepidolite, pedalite, spodumene and amblygonite are the most important minerals containing lithium. Seawater, which contains 230 billion tons of lithium in total, has recently been paid attention as possible resource of this element.
The lithium content in the drinking water is variable from 0.1 ppb to 100 ppm. High lithium concentration is possible to find in some groundwater and mineral waters. Higher concentrations of lithium are also accompanied by higher concentration of sodium usually. The usual lithium concentration in the common surface water is about 10 ppb. Lithium has no limitations in the directives dealing with drinking, surface and supply waters usually. The irrigation waters have the limitation sometimes, since the lithium is cummulated in the plants and inhibit their growth. The limitations vary between 2-5 ppm. The high lithium content in the mineral waters has a balneological impact, since it prevents the risk of the coronary illnesses. Another important impact of lithium content in the drinking waters is a positive influence on the human nervous system; it diminishes some mental diseases accompanying the aggressive manners.
Water source | Concentration range in ppm | Country |
Drinking (surface) | 0.002 - 0.017 | Czech Republic |
Drinking (groundwater) | 0.0047 - 0.020 | Czech Republic |
Drinking (mineral) | 0.1 - 13 | Czech Republic |
Mineral | 3-6 | Romania |
Mineral | 4.87-8.00 | USA |
Volcanic | 10-46 | Turkey |
Volcanic | 0.1-44.2 | Mexico |
Lithium concentration profiles in the seawater - Republic of Palau(A,B) and Fiji (C,D) |
Name, Formula | Li content | Colour | Hardness | Density | Luster | Crystal system | Diaphaniety | Fracture |
Spodumene LiAlSi2O6 |
3.73 wt.% | grayish white, pink, violet, emerald green, yellow | 6.5-7 | 3.1-3.2 | vitreous (glassy) | monoclinic-prismatic | transparent to translucent | splintery-thin |
Petalite LiAlSi4O10 |
2.09 wt.% | colorless, gray, yellow, yellow gray, white | 6-6.5 | 2.39-2.46 | vitreous-pearly | monoclinic-prismatic | transparent to translucent | brittle-conchoidal |
Amblygonite (Li,Na)AlPO4(F,OH) |
3.44 wt. % | white, yellow, gray, bluish gray, greenish gray | 5.5-6 | 2.98-3.11 | vitreous-pearly | triclinic-pinacoidal | transparent to subtransparent to translucent | uneven |
Lepidolite K(Li,Al)3(Si,Al)4O10(F,OH)2 |
3.58 wt.% | colorless, gray white, lilac, yellowish, white | 2.5-3 | 2.8-2.9 | vitreous-pearly | monoclinic | translucent | uneven |
Zinnwaldite KLiFe2+Al(AlSi3)O10(F,OH)2 |
1.59 wt.% | light brown, silvery white, gray, yellowish white, greenish white | 3.5-4 | 0.9-3.1 | vitreous-pearly | monoclinic-prismatic | transparent | uneven |
Eucryptite LiAlSiO4 |
5.51 wt.% | brown, colorless, white | 6.5 | 2.67 | vitreous (glassy) | trigonal-rhomboedral | transparent to translucent | brittle-conchoidal |