Вестник МГТУ. 2019, Т. 22, № 1.

Сорохтин Н. О. и др. Первая находка алмаза на полуостровах Средний и Рыбачий. Chromium diopside occurs as single half-rounded pale-green fragments and single angular-shaped debris. The surface of the debris is coarse-grained, each fragment has conchoidal fractures. The size of particles is about 0.3 mm. The debris gabitus is prismatic mainly (Fig. 10). The content of Cr2O3is about 1 %, which is verified by the microprobe analysis (Table). Fig. 10. Fragments of chromium-diopside crystals Рис. 10. Осколки кристаллов хром-диопсида Chromium-spinellid is found as a single particle in the alluvial sample on the right side. It is 0.1 mm big, octahedron-shaped and dark brown (Fig. 11). Verified by the microprobe analysis (Table). Fig. 11. Fragments of chromium-spinellid crystals Рис. 11. Осколки кристаллов хром-шпинелида Zircon occurs mostly as fine (about 0.1-0.2 mm) elongated crystals or rare pale-pink debris. The content in samples is about 1.5-2 % of the heavy fraction weight. Rutile occurs mostly as fine (0.1-0.2 mm) elongated or round black or deep red crystals. The content in samples is about 0.5-1 % of the heavy fraction weight. Ilmenite occurs mostly as irregular rounded and angular-shaped grains with a size of 0.1 to 0.5 mm. The content in samples is about 1-3 % of the heavy fraction weight. 44