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Zircon crystals from crushed syenite samples of individual intrusive bodies in the Velyka Vyska Massif were studied using the SEMEDS (BSE images and chemistry) and SIMS methods. The results obtained were compared with early published data for zircon from the Azov and Yastrubets syenite massifs, Ukrainian Shield that host ZrREE mineralization published earlier. Most of the zircon crystals analyzed are chemically inhomogeneous, but either azonal or show poorlydefined regular zoning. A darker

The paper considers a three-stage technology for angular rolling of the pipe workpiece. This technology facilitates the expansion of the range of flange parts available by eliminating a number of drawbacks of the known methods of metal forming. In the presented paper, we analyze the results of numerical calculations and experiments, as well as the effective deformation values in blank material, using computer simulation in the DEFORM-3D software package. The results of the computer simulation were reached taking into account experimental studies of the rheological properties of copper alloy L68 in the form of a strain hardening curve using the Instron-8850 complex. The results of the ratio of basic geometric dimensions expanded the range of flange parts under investigation and allowed us to consider angular rolling technology with a variable angle of inclination of the rolling roll from a three-stage perspective, especially in small-scale production.

An adequate computer model of the process of rolling flange details with inclined rolls has been built in the software package DEFORM-3D. The analysis of the stress-strain state of a detail with a flange was performed. The rheological properties of the alloy L63 (62-65% Cu, 34.5-38% Zn) were experimentally studied. Value limits of the Cockcroft-Latham fracture criterion for the alloy L63 are determined.

Data on the content and distribution of trace and rare-earth elements (SIMS method) in sectors and growth zones of a large zircon crystal from miaskite pegmatites of the Vishnegogorsky massif are presented. The morphology of the zircon crystal is a combination of a dipyramid {111} and prism {010}. It has been established that the growth sector of dipyramid {111} is characterized by almost one order of magnitude higher contents of Y, Nb, REE, Th; higher Th/U and Eu/Eu* values; REE distribution spectra are flatter compared to prism {010} growth sector. A regular decrease in the content of trace and rare-earth elements in the direction from the central zone to the marginal zone of crystal growth was revealed. A smooth regression of zircon crystallization temperature of zircon from 960 °C in the central zone to 740 °C in the marginal zone of the dipyramid sector and 700-650 °C in the prism sector has been revealed, which may be a reflection of thermal evolution of the crystallization process. It is assumed that crystallization of the central zone of zircon occurred at early stages from a relatively trace-еlement-rich melt. The crystallization was completed at lower temperatures, probably, simultaneously with the formation of REE-concentrating minerals, which resulted in natural decrease of  content of trace and rare-earth elements in the melt and, consequently, in zircon crystallizing from it.