Granulometry of diamonds in the Perm territory according to prospecting data in the 1940s - 1970s

Abstract

The distribution curves of the equivalent diameters of diamonds from modern placers in the Cis-Urals are close to the normal law and have two dimension peaks: in the intervals 2 - 3 and 4 - 5 mm, i.e. placer diamonds come from two sources. A peak of smaller size characterizes the dimension of diamonds of not yet identified kimberlites - a kimberlite peak, the second peak of larger diamonds is characteristic of secondary reservoirs - a peak of collectors. In the modern placers of the Northern Urals, diamonds come from two sources, in the modern placers of the Middle Urals, diamonds from secondary reservoirs predominate.