I. S. Barmin, Deputy Director for Technical Development, L. N. Akhmetshina, Deputy Head of the Dressing Complex, D. V. Zabal'sky, Head of the Section of the Dressing Complex, D. V. Stepannikiov, Deputy Chief of PKO, "Kovdorsky GOK" JSC; E. P. Lokshin, Chief of the Laboratory of the Institute of Chemistry and Technology of the Rare Elements and Raw Minerals KNC RAN, Doctor of Technical Science