TY JOUR TI Mineralogical features of tungsten ores affecting their processability KW scheelite ore KW scheelite KW tungstite KW mineralogical features JO Vestnik of geosciences AU Zhukova, V.E. AU Ozhogina, E.G. AU Sycheva, N.A. AU Shuvalova, Y.N. PY 2026 IS 0 PB FSBI FIC "Komi Scientific Center of the Ural Branch of the Russian Academy of Sciences"