Инд. авторы:	Nekipelova A.V., Sokol E.V., Kokh S.N., Khvorov P.V.
Заглавие:	Rare Earth Phosphates in the Kerch Caviar Ironstones
Библ. ссылка:	Nekipelova A.V., Sokol E.V., Kokh S.N., Khvorov P.V. Rare Earth Phosphates in the Kerch Caviar Ironstones // Russian Geology and Geophysics. - 2021. - Vol.62. - Iss. 10. - P.1188-1207. - ISSN 1068-7971. - EISSN 1878-030X.
Внешние системы:	DOI: 10.2113/RGG20214359; WoS: 000710871700007;
Реферат:	eng: The mineralogy and contents of major and trace elements (including REE+Y) in bulk samples and separate size fractions of caviar-like ironstones from the Kamysh-Burun deposit (Kerch iron province) are studied to estimate the contributions of different REE+Y species to the total budget. The analyzed ore samples contain MREE adsorbed on Fe3+-(oxy)hydroxides, as well as LREE authigenic phosphates. The predominant rhabdophane-type (Ce(PO4)center dot nH(2)O) phases are enriched in La, Pr, Nd, and Ca, depleted in Ce, and free from Th. The REE carriers belong to solid solution series of two main types: LREE(PO4)center dot nH(2)O - (Ca,Ce,Th)(PO4)center dot H2O (rhabdophane-like phase and brockite) or LREE(PO4)center dot nH(2)O - (Ca,U,Fe3+)((PO4),(SO4))center dot 2H(2)O (rhabdophane-like phase and tristramite). REE phosphates occur most often in the <= 0.25 mm fractions of ironstones, where average and maximum Sigma REE contents (X-av = 606-1954 ppm; X-max = 769-3011 ppm) are comparable with the respective amounts in the Chinese industrial clay-type REE deposits. The Kerch ores are commercially attractive unconventional resources of highly demanded Pr and Nd: they can be extracted at relatively low costs, due to high Pr/Ce and Nd/Ce ratios, while low Th and U reduce the environmental risks from stockpiled wastes.
Ключевые слова:	MINERALIZATION; ELEMENTS; BAYAN OBO; MN-OXIDES; REE DEPOSITS; WESTERN DESERT; OOLITIC IRONSTONES; BAHARIYA DEPRESSION; IRON-ORES; unconventional REE resources; tristramite; Pr, Nd, rhabdophane; authigenic LREE phosphates; rare earth elements (REE); Kerch ooidal ironstones; GEOCHEMISTRY;
Издано:	2021
Физ. характеристика:	с.1188-1207