“Severalmaz” Company (Arkhangelsk, Russia):

Grib P. V., Head of a Diamond Sorting Shop, e-mail: PGrib@severalmaz.ru

The operations, which are held with diamonds in the diamond-sorting shop, in “Severalmaz” company, are the final study of the diamond ore processing, during the beneficiation process. Diamond raw materials are delivered in diamond-sorting shop from the final concentration department and pass a necessitate development cycle: sizes range control, selection of impurities, evaluation of diamond safety, dividing on the size and weight groups and conditionally screen classes with an account of the crystals quantity in each size, express mineralogical study, presorting and expert valuation. Experts of a diamond-sorting shop hold an analysis of the cost estimation characteristics of diamonds and its changes for the appointed extraction periods. The analysis is held according to the results of sorting and evaluation of diamond raw materials, in which there are taken into account the form (crystallographic form, effective age, desorption degree, relief of borders), defect structure and color of diamonds. The near jeweler grade diamonds are dominate in the Arkhangelskaya pipe of Lomonosov deposit (to 67% of mass of the extracted raw materials). Also, there is the significant quantity of unapplicable diamonds for making the jewelery – the industrial diamonds (16-18%). The juwellery makes the 15% of the whole mass of the extracted production.