Vanadium and Cobalt Occurrence in the Fe-Ti-V Oxide Deposits Related to Mesoproterozoic AMCG Complex in NE Poland  
[PERSON]  
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[PERSON]  
[PERSON] and [PERSON]  
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Polish Geological Institute--National Research Institute, Rakowiecka 4, 00-975 Warszawa, Poland; [EMAIL_ADDRESS] (K.S. ); [EMAIL_ADDRESS] (Q.W. ); [EMAIL_ADDRESS] (R.M.) 1  
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kets; these are sediment-hosted stratiform Cu deposits, Ni-bearing laterite deposits, and magmatic Ni-Cu-Co sulphide deposits hosted in mafic and ultramafic rocks [6]. During magma crystallization, cobalt behaves similarly to nickel, crystallizing in sulphides. The main carrier of cobalt is pentlandite (_Ni_, _Fe_, _Co_)\({}_{9}\)_S_s, in which the Co content ranges from below one to several percent by weight. The average content of cobalt in igneous rocks is 23 ppm [7]. The rocks that are richest in Co are ultrabasic rocks, dunites, and peridotites (127-148 ppm Co), whereas norites and gabbros contain on average 50 to 60 ppm Co, and granites contain approximately 5 ppm [7]. In the hydrothermal stage, a large group of cobalt sulphides, arsenides, antimonides and arsenic, and antimony sulphides are formed. The most common among these are cobaltite (up to 36 wt% Co), glaucodot (up to 31 wt% Co), danaite (3-10 wt% Co), safflorite (\(\sim\)28 wt% Co), skutterudite (up to 30 wt% Co), sigenite (20-30 wt% Co), bravoite (up to 6 wt% Co), and costibite (\(\sim\)27 wt% Co). Vanadium is one of the most important alloying additives in the production of full-alloy and high-strength low-alloy steels. The average vanadium content in the continental crust is high, at approximately 150 ppm [8]. Vanadium occurs through isomorphic substitution in numerous minerals, but these minerals are disseminated as accessory minerals in rocks. Among the orthomagnatic deposits, which are genetically related to ultrabasic (dunite) and basic rocks (gabbro, norite, and anorthosite), the content of V\({}_{2}\)O\({}_{5}\) ranges from 0.2 to 2 wt%, respectively. The main V carriers in these deposits are generally titanium-rich magnetite (_Fe_\({}^{2+}\) (_Fe_\({}^{3+}\)_, _Ti_)\({}_{2}\)O\({}_{4}\)) and ulvospinet (_TiFe_\({}_{2}\)O\({}_{4}\)) and ilmenite (_FeTiO_). Vanadium (V\({}^{3+}\)) forms a spinel-coulsonite (_V\({}_{2}\)FeO_\({}_{4}\)) an isomorphic series with other spinels, such as magnetite and chromite, and therefore Fe\({}^{3+}\) may be substituted by V\({}^{3+}\) in these minerals. Considerable admixtures of V\({}^{3+}\) or V\({}^{4+}\) are present in dark rock-forming minerals [8]. In orthomagnatic Fe-Ti(-V) deposits, a typical grade of titanomagnetite ore is 0.2-1 wt% V\({}_{2}\)O\({}_{5}\) (max. 1-2 wt%) [8]. The world's resources of vanadium exceed 63 million tons [6]. Additional sources of vanadium are titaniaferous magnetite, phosphate rock, traniferous sandstone and siltstone, bituminous sands, and heavy crude oil [6]. One of the main types of vanadium-supplying deposits is orthomagnatic Fe-Ti-V oxide, which is accompanied by sulphide mineralization. The presence of polymetallic sulphides (Fe, Cu, Co, and Ni) in this type of deposit can also be a source of cobalt, which can be present in the form of its own sulphides and isomorphic substitutions in other sulphides. This type of Fe-Ti-V deposit was documented in NE Poland in the 1960s up to the 1980s. However, detailed data on the economic potential of these deposits for critical elements were poorly provided during exploration. Hence, the aim of this study was to determine the whole rock contents of V and Co in mineralized samples from the Krzemianka and Udryn Fe-Ti-V deposits in the Suwalki Anorthosite Massif (SAM) in Poland.