Element Tantalum, Ta, Transition Metal

The discovery of transition metal tantalum is closely related with extraction of niobium. One year later after 1801, when Charles Hatchett found a new element, niobium, which he named columbium, Anders Gustaf Ekeberg investigated minerals from Ytterby and other mines in northern countries similar to the columbite. He extracted an oxide of a new element which turned out to be acid resistant though soluble in alkali. Following Klaproth's method he named it tantalum symbolizing oxide is insoluble in acid, and was unable, just as the mythological Tantalos, "to quench his thirst". Ekeberg called the ores in which tantalum was discovered tantalite and yttrotantalite. Perhaps Ekeberg isolated impure tantalum. In 1809 William Hyde Wollaston claimed to have shown Hatchett's columbium and Ekeberg's tantalum were identical.

Tantalum crustal abundance is 2.5x10^-4 mass %. Its presence is typical for granite ad sedimentary layers with average concentration 3.5x10^-4%. Deep layers and upper mantle are poor by tantalum, 1.8x10^-6% in ultrabasic rocks. Tantalum is dispersed in most of magmatic rocks and biosphere, its concentration remains not determined. 17 own ores and more than 60 tantalum containing minerals are known. All of them are products of magmatic activity (tantalite, columbite, loparite, pyrochlore etc.). Tantalum in ores is associated with niobium as a consequence of the physical and chemical properties similarity. Tantalum ores are deposited in pegmatites of granite and alkali rocks, in carbonate and hydrothermal veins as well as in placers which are most commercially important.