The Nyurba Diamond Field was discovered in 1996, and it is a highly-diamondiferous primary diamond deposit with considerable ore reserves. The mean diamond concentration is more than 5.7 carats per tonne. The diamondiferous kimberlite pipe Nyurbin was discovered during land-based and aeromagnetic surveying in an area of 100 square kilometers in the vicinity of the Botuobin pipe.

The field is on the territory of the Nakyn kimberlite field, which is part of the Sredne-Marhinsky kimberlite area.

The Nyurbin pipe is on the watershed of the Hannya-Nakyn River within an axial line of the Dyakhtarsky break, in the south of which the Botuobin pipe is located. Both of these pipes are buried kimberlite bodies. The thickness of the overlapping deposits of the Nyurbin pipe is 57 to 61 meters. With respect to the buried relief, this pipe has an elliptical form of submeridional orientation with the measurements 300-320 õ 130-160 meters. In a vertical cut, the pipe morphology is close to the diameter of the cylindrical-type conduit. The slope angle of the pipe surfaces ranges from rather flat (75-80î) to subvertical (85-87î). The ore body of the pipe is combined with autolithic kimberlite breccia. On the basis of preliminary data from the core samples, it has been established that diamond concentrations in the kimberlites in the boreholes fluctuate on average more than 5.7 carats per tonne, and with regard to mineralogical and qualitative characteristics, they are comparable to Botuobin pipe diamonds.

The adjacent strata of the Nyurbin kimberlite pipe consist of sedimentary rock of the upper Cambrian Markhin Formation (E3 mr) and according to the sedimentary rock deposited on them, the lower Ordovician Oldondin Formation (O1 ol).

In March 2000, the Nyurbin mining and processing combine was established in order to develop the Nyurbin and Botuobin pipes.

The strategic plan for the development of the Nyurbin mining and processing combine is based on the principle of minimizing preparation time for operation of fields. Reducing the preparation times was accomplished on account of combining the exploration and prospecting stage, preliminary and detailed geological surveying and simultaneous geological research.

The diamond-preserving, non-explosive method of extraction of loosening with heavy bulldozers is applied at the Nyurbin kimberlite pipe.

Construction of the basic mill of the combine – No.16 – started in 2002. Construction of the mill lasted only 530 days, and it was commissioned on August 23, 2003. The mill’s productivity is 1.5 million tonnes of ore per year. The sum of international experience was considered in its design. The mill’s design includes the use of autogenous and classification – standard type of ore treatment for Alrosa – as well as a high-pressure roll press. Beneficiation is conducted in heavy media, separately according to size classes -32 +6 mm and -6 +1 mm, with the subsequent operational development of a concentrate of x-ray-fluorescent and fat separation. Application of the processes heavy-medium separations allows considerable relief of the load on the recovery plant, which facilitates stable operation and a high rate of diamond extraction. In terms of the applied technologies and the degree of automation of processes, the mill is one of the advanced in the international diamond-mining industry.

The building, field operation, and diamond ore treatment techniques used at the Nyurbin mining and processing combine have received the highest environmental compatibility rating. According to scientists of the Institute of the Applied Ecology of Environmental Impact, the combine has no emissions and dumping of pollutants in environment in excess of established limits, and there is no above-limit waste disposal. This affords the combine the status of an environmentally safe manufacturing facility.

The Nyurbin mining and processing combine has the highest natural diamond extraction growth rates in Alrosa. In 2002, $85 million of principal product was extracted at the site, with $191 million in 2003, $390 million in 2004, $529 million in 2005 and $572.3 million in 2007.