Roman Andreevich Nefedov

3.2. Air Classification Air separation was carried out on a zircon sample weighing 10 kg. As a result of the air separation, six fractions were obtained. The fractions were marked as they left the air-centrifugal separator. The yield of fractions and their physical characteristics are presented in Table 2. Table 2 shows that the centrifugal air separation allowed for separating the fractions by increasing the bulk and actual density.

3.2. Radioactive Elements and Their Forms in the Ore of the Yuzhno-Bogatyrskoye Occurrence (Kuznetsk Alatau) Orthite is the most widely spread mineral in the specimens under study: its content is 90%–96%. According to the polished sections, orthite can be classified into two groups. The orthite of the first generation is represented by isometric or elongated crystals with a length-to-width ratio of 2:1 and 3:1. The crystals with the prismatic habitus in the cross-section resemble hexagonal prisms.