Database of Rare Element Minerals of Ukraine

It is shown that the concept of "rare elements" is rather conditional. The list of rare elements, as well as their selection criteria, constantly changed over time. Geochemical and mineralogical criteria gradually became closely connected with technological and economic criteria. Such criteria as insignificant distribution in the earth's crust, weak mineral formation, and the lack of large deposits were joined by technological difficulties of extraction, minimal use in technology, unprofitable extraction, or artificial shortages due to monopolization of reserves by supplying companies. The list of critical mineral raw materials, which is based on rare chemical elements, is growing every year, with almost all the elements with a clarke of less than 100 ppm being in short supply. This encourages mineralogists to look out for a wider range of carrier minerals of rare elements than it was before, thus expanding the list of rare elements. It is reasonable to group carrier minerals of rare elements not by geochemical, but by chemical properties of the elements, since similar properties are crucial for their use in the same industries. The mineral database of Ukraine includes about 900 mineral species, and in six hundred of them rare elements are species- and speciation-forming. It is suggested to divide them into the following groups: minerals of alkaline (Li, Rb, Cs), alkaline earth (Be, Sr, Ra), transition (Sc, Zr, Hf, V, Nb, Ta, Mo, W, Re, Cd, and Hg), amphoteric (Ga, In, Sn, Tl, Bi), noble (Pt, Ru, Rh, Pd, Os, Ir, Au, Ag), rare earth (Y, La, Ce and other lanthanides) and radioactive (Th, U) metals, semi-metals (B, Ge, As, Sb, Te), non-metals and halides (Se, Br, I). The database should be supplemented with minerals of such low-clarke transition elements as Cu, Co, Cr, Ni, Zn, and Pb, which are predicted to be the elements of the future. Mineral resources of Ukraine contain significant potential for expanding the database of rare element minerals and increasing the reserves of critical raw materials.