Primary diamond deposits of the Siberian craton: geology, petrology and mineralogy insights

We provide general data on all the primary diamond deposits of Siberian craton, including the names of pioneers, the size of pipes, volume models for pipe bodies, interior features, and the diamond grade of kimberlites. The U-Pb ages of the deposits are within 350–370 Ma. The pipe's features are different by morphology, they may be both single-feeder and multi-feeder, with crater funnel-shaped expansion at the pipe tops, and subcylindrical having (starting from the surface) sub-vertical walls. The diamond grade gradually decrease from southern to northern deposits within Yakutian Province (the highest diamond grade for the Nakyn and Mirninsky fields, moderate for the Daldyn and Alakit-Markha fields, and relatively low being at the Upper Muna field occupying the most northern position as compared to with the other fields). The diamond grade of deposits correlates with the chemical composition of kimberlites. The highest diamond grade is noted at the Nyurbinskaya, Botuobinskaya Mayskaya, Internatsional'naya, and Aikhal pipes which are composed of high-Mg kimberlites. Most Yakutian deposits are composed mainly of volcanoclastic kimberlites that usually are higher diamond-grade, as compared with the coherent kimberlites. We discuss genetic issues of different morphology and multiphase composition of kimberlite pipes as well as rates for different intrusion phases and duration of pipe formation. The origin of some species of pyroclastic kimberlite is supposed to be related to the mantle depths.