Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, IGEM RAS (Moscow, Russia)

Makeyev А. B., Doctor of Geological-Mineralogical Sciences, Professor, Leading Researcher, abmakeev@mail.ru

N. P. Yushkin Institute of Geology, Komi Scientific Center, Ural Branch of RAS (Syktyvkar, Russia)

Lyutoev V. P., Candidate of Geological-Mineralogical Sciences, Leading Researcher, vlutoev@geo.komisc.ru

A. V. Shubnikov Institute of Crystallography, of the Kurchatov Complex Crystallography and Photonics, of the NRC “Kurchatov Institute” (Moscow, Russia)

Starchikov S. S., Candidate of Physical-Mathematical Sciences, Leading Researcher, sergey.s.starchikov@gmail.com

A. A. Baikov Institute of Metallurgy and Materials Science, IMET RAS (Moscow, Russia)

Zablotskaya Yu. V., Candidate of Technical Sciences, Senior Researcher, yuliaz20212@gmail.com

Six samples of magnetic concentrates of the giant Pizhemskoye true titanium pseudorutile–leucoxene–quartz deposit, Middle Timan, were studied. Among them are: primary (KRP12, KRP27, SRP12); sample SRP18 after their hydrochloric acid treatment to dissolve siderite; and samples (SRP11, KRP05) of commercial products after autoclave (~520K) leaching of silicon dioxide. The chemical composition of the samples was determined by X–ray fluorescence analysis, and the normative recalculation of these analyses provides a preliminary idea of their mineral composition. The composition of iron–containing phases was studied using ⁵⁷Fe Mössbauer spectroscopy. It was established that, along with the dominant pseudorutile phase, the samples contain ilmenite and siderite. Additionally, it was shown that at a temperature of 27K, pseudorutile undergoes a transition to a magnetically ordered state of the spin glass type. It was found that during the modification process (HCl treatment) and in the autoclave enrichment process, the phase composition of the concentrates changes towards a decrease in ilmenite and an increase in the proportion of pseudorutile. This allowed for the characterization of the phase composition of commercial products.
The authors are sincerely grateful to the staff of the IGEM RAS I.A. Morozov and A.I. Yakushev for their assistance in analytical research.
Sampling of magnetic concentrates and conducting X–ray phase and X–ray fluorescence analysis were carried out within the framework of the state assignment of IGEM RAS No. 124022400144–6.
Removal of siderite and desiliconization of quartz–titanium concentrates were carried out within the framework of the state assignment of IMET RAS.
⁵⁷Fe Mössbauer spectroscopy measurements were carried out within the state assignment of the NRC “Kurchatov Institute”, Mössbauer spectra analysis was carried out at the IG FIC Komi SC of the Ural Branch of the RAS within the framework of the research topic 1220440600009–2.

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