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Determination of diamondiferous placer primary sources by the ratio of nitrogen traces and carbon isotope composition in South African diamonds

https://doi.org/10.52349/0869-7892_2025_102_139-147

Abstract

South Africa locates both primary sources of diamonds (kimberlite pipes) and the pipe washout induced placers. Notably, the range of the region’s placers is incredibly wide: from alluvial to coastal-marine, marine, and wind-formed. In the paper, the author attempted to analyze nitrogen traces content and carbon isotope composition in the region’s diamonds to develop a new method for determining primary sources of the region’s placer diamonds. Although researchers (both foreign and Russian ones) characterized the diamond properties, they did not analyze connections between placer diamonds and pipes, using these parameters. The current paper is novel in this respect. This method of comparing placer diamonds and their sources requires further development by applying a wider data range both for this region and verifying it on primary and placer diamond sites in other regions.

About the Author

O. N. Malykh
All-Russian Geological Research Institute of A. P. Karpinsky
Russian Federation

Oleg N. Malykh, Leading Engineer

Saint Petersburg



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Review

For citations:


Malykh O.N. Determination of diamondiferous placer primary sources by the ratio of nitrogen traces and carbon isotope composition in South African diamonds. Regional Geology and Metallogeny. 2025;32(2 (102)):139-147. (In Russ.) https://doi.org/10.52349/0869-7892_2025_102_139-147

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