Element Lithium, Li, Alkali Metal
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Lithium History
Lithium was discovered by a Swedish chemist and mineralogist Johan August Arfwedson (1792 - 1841), when he was an assistant in the laboratory of Jons Jakob Berzelius. Arfwedson was running chemical analysis of the petalite ore (LiAl(Si2O5)2) and supposed that it contains a new alkali element. He noticed that its compounds resembled the compounds of sodium and potassium; however its carbonate and hydroxide are less water soluble. Arfwedson offered the name "lithium" (Greek "lithos" meaning "stone") showing its mineral descent. He also showed that this element is found within the minerals spodumene (also called silicate pyroxene) LiAlSi2O6 and lepidolite (lithium-mica) with composition K2Li3Al4Si7O21(OH,F)3. The element was named by Sir Humphry Davy who used electrolysis on lithium oxide in 1818.
Lithium Occurrence
By its geochemical properties lithium belongs to Alkali Metals large-ion lithophile elements which also include potassium, rubidium, and caesium. Its concentration in upper continental crust is 21 g/t. Lithium is contained particularly in the minerals lepidolite KLi1,5Al1,5[Si3AlO10](F, OH)2 (Li-mica) and pyroxene spodumene LiAl[Si2O6]. As soon lithium does not form independent minerals it isomorphously replaces the potassium in rock-forming minerals. Lithium deposits are associated with rare metal-related granite intrusions with which Lithium-bearing pegmatite and hydrothermal complex deposits also containing among others various metals such as tin, tungsten, bismuth, are associated. A very special mineral, ongonite, which is magmatic topaz-rich granite with high concentrations of fluorine and water and extremely high concentration of rare earth metals, including lithium, is worth a specific mention. Brines of some strongly salt lakes are other kind of deposit.
Lithium is one of the bioelements which always occur in living organisms. Until recently the physiological importance of this element was unexplored. In 1980 it was shown that the deficiency of lithium leads to liveweight gain deceleration. So the vital necessity of lithium has been proved.
Lithium Neighbours
Element Periodic Table | | | |