Mineralogy of diamonds from the Ozernaya pipe, Ottorzhenets body, Pervomaiskaya and Novogodnyaya veins, Yakutia

Abstract

The paper presents the results of a comprehensive mineralogical study, including IR and UV spectroscopy, of diamonds and related solid inclusions from kimberlitic bodies and veins located adjacent to the Yubileinaya pipe, the largest (59 ha) in the Siberian Platform. This pipe is characterized by a complex structure with diatreme and crater facies of kimberlitic magmatism. The typomorphic features of diamonds from the Ozernaya kimberlitic pipe, Pervomaiskaya and Novogodnyaya veins, and Ottorzhenets kimberlitic body, as well as the Carboniferous-Permian terrigenous sedimentary rocks that overlie the Yubeleinaya pipe, are described and compared with those of the Yubileinaya pipe. The typomorphic features of diamonds from the earliest phase of kimberlitic magmatism are emphasized. Diamonds from the Ozernaya pipe are similar to those from the Komsomol’skaya pipe, which is characterized by a low content of typical round crystals and a high content of eclogite-type inclusions in high-quality diamonds of variety I after Yu.L. Orlov. The typomorphic and genetic features of diamonds testify to the multiphase nature of the kimberlitic magmatism of Middle Paleozoic age (about 360 Ma ago). These features are discussed in terms of variation in diamond genesis and types of this mineral.