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As a result of a comprehensive study of the geological structure and diamond presense of the northern part of the East European Platform, generalization of the data accumulated by various organizations in the USSR, the Russian Federation, and other states, three main prospecting models of primary diamond deposits have been identified and characterized: Karelian, Finnish, and Arkhangelsk. Geological, structural, mineralogical, and petrographic criteria of local prediction, as well as the features of the response of kimberlite and lamproite bodies in dispersion haloes and geophysical fields, are considered using known examples, including data on the developed M.V.Lomonosov and V.P.Grib mines. It is shown that the most complicated prospecting environments occur in the covered areas of the Russian Plate, where, in some cases, the primary diamond-bearing rocks are similar in their petrophysical properties to the host formations. The buried dispersion haloes of kimberlite minerals in the continental Carboniferous and Quaternary deposits are traced at a short distance from the sources. Differences in the prospecting features of magnesian (Lomonosov mine) and ferromagnesian (Grib mine) kimberlites are also shown. Conclusions about the diamond potential of the model objects of various types are given in this paper.

The article describes the history of studying the diamond content of tectonic structures of the territory of Belarus. Based on the results of magnetometric, mineralogical, tectonic studies carried out by industrial geologists and scientists over the past 50 years, new scientifically substantiated criteria for the search for explosion pipes have been developed using Clifford’s rule, according to which kimberlite explosion pipes are developed within the Archean cratons, where the thickness of the lithosphere is 175–270 km, and are absent in the zones of Early Proterozoic stabilisation and tectonomagmatic activation. Explosion tubes on the African-Arabian, East Siberian, Sino-Korean and East European platforms demonstrate their confinement to the Archean cratons and may be associated with zones of paleosubduction of the Proterozoic oceanic crust beneath the Archean cratons. Based on this, the authors scientifically substantiated the hypothesis that during the closure of the Early Proterozoic paleoocean separating the Fenno-Scandinavian craton from the Volga-Ural and Sarmatian cratons, subduction of the younger crust took place under these cratons, the southwestern corner of which on the territory of Belarus is the Vitebsk granulite massif. The article concludes that the Vitebsk granulite massif is the most promising in terms of diamond-bearing on the territory of Belarus, and within its limits – the Smolensk regional deep fault at the intersection of this fault of northeastern striking with the Odessa-Gomel regional deep fault of submeridional striking south of the city of Orsha. Recommendations are given for further study of promising areas in order to determine their diamond content.

The article presents the results of prospecting of diamond boring within the Kuhotsko-Bilska area, which is located on the north-western slope of the Ukrainian Shield.The data of the researches of 1995–2013 made it possible to form a new view on regional and local criteria and signs of diamond-bearing area of work, including a detailed study of the material composition of breccia, to distinguish among them explosive, to discover a new type of potentially diamond- bearing structures.According to all available geological and geophysical information, specific recommendations are given for direct searches for kimberlite or lamproite bodies within promising structures and breccia occurrence.

We have studied mineral and chemical composition of lamproites from Kalymbaevsky Complex the Middle Trias. These lamproites were developed in Magnitogorsk and Eastern-Urals megazones of the Southern Urals. We have established the presence of olivine, phlogopite, diopside phenocrysts. We have registered the presence of globular structures, consisting of sanidine and interstitial glass. We have also shown the presence in the base of rocks microlites of aluminous diopside-augite and alkaline pyroxenes of aegirin-augite series, which previously were taken for alkaline and sub-alkaline amphiboles. We have established high sulfur concentration in the apatite which, without magmatic sulfides in the rocks, witnesses for oxidation of lamproite magmas. For the first time precise geochemical data for microelemental and isotopic Sr, Nd composition of rocks are given. It was found that the South Urals rocks have a intermediate composition between lamproites and potassium alkaline basalts. Their source was the enriched mantle with the value εNdi = +0.7-+3.9. We have shown uncertainty of geochronological data, according to which lamproite magmatism could be initiated 197-240 or 300-310 Ma.

We have studied mineral and chemical composition of lamproites from Kalymbaevsky Complex the Middle Trias. These lamproites were developed in Magnitogorsk and Eastern-Urals megazones of the Southern Urals. We have established the presence of olivine, phlogopite, diopside phenocrysts. We have registered the presence of globular structures, consisting of sanidine and interstitial glass. We have also shown the presence in the base of rocks microlites of aluminous diopside-augite and alkaline pyroxenes of aegirin-augite series, which previously were taken for alkaline and sub-alkaline amphiboles. We have established high sulfur concentration in the apatite which, without magmatic sulfides in the rocks, witnesses for oxidation of lamproite magmas. For the first time precise geochemical data for microelemental and isotopic Sr, Nd composition of rocks are given. It was found that the South Urals rocks have a intermediate composition between lamproites and potassium alkaline basalts. Their source was the enriched mantle with the value εNdi = +0.7-+3.9. We have shown uncertainty of geochronological data, according to which lamproite magmatism could be initiated 197-240 or 300-310 Ma.

Calculations shown that a relatively low-temperature kimberlite magmas consolidated with decompression exploded on significant depth and formed pipes. High-temperature lamproite magmas exploded on near-surface conditions and formed mainly tuff covers. Their erosion formed diamond placers. Kimberlite magmas and their diamonds are a result of fractionation peridotite layer of magma ocean. Lamproite magmas and their diamonds are a result of fractionation of magmatic chambers in plumes. Non-kimberlite diamons of placers have lamproite plume genesis.

Calculations shown that a relatively low-temperature kimberlite magmas consolidated with decompression exploded on significant depth and formed pipes. High-temperature lamproite magmas exploded on near-surface conditions and formed mainly tuff covers. Their erosion formed diamond placers. Kimberlite magmas and their diamonds are a result of fractionation peridotite layer of magma ocean. Lamproite magmas and their diamonds are a result of fractionation of magmatic chambers in plumes. Non-kimberlite diamons of placers have lamproite plume genesis.