Vladimir Kozlov - Academia.edu (original) (raw)

Papers by Vladimir Kozlov

Research paper thumbnail of Vymazalováite, Pd3Bi2S2 , a new mineral from the Noril'sk -Talnakh deposit, Krasnoyarskiy region, Russia 2 3

Mineralogical Magazine (2018) 82 (2): 367–373, 2018

Vymazalováite, Pd3Bi2S2 is a new platinum-group mineral discovered in the Komsomolsky mine of the... more Vymazalováite, Pd3Bi2S2 is a new platinum-group mineral discovered in the Komsomolsky mine of the Talnakh deposit, Noril’sk district, Russia. It forms small (from a few μm to 20–35 µm) inclusions or euhedral grains in intergrowths of polarite, sobolevskite, acanthite and unnamed (Pd,Ag)5BiS2 in aggregates (up to ~200 µm) in galena and rarely in chalcopyrite. It occurs with telargpalite, cooperite, braggite, vysotskite, sopcheite, stibiopalladinite, sobolevskite, moncheite, kotulskite, malyshevite, insizwaite, Au-bearing silver and the newly described mineral kravtsovite (PdAg2S) in association with pyrite, chalcopyrite and galena in vein-disseminated mineralization in skarn rocks. Synthetic vymazalováite is brittle; it has a metallic lustre and a grey streak. In plane-polarized reflected light, vymazalováite is creamy grey and appears slightly brownish against galena in the assemblage with chalcopyrite. It exhibits no internal reflections. Average reflectance values in air for natural and synthetic vymazalováite are (R natural, R synthetic in %) are: 46.35, 45.7 at 470 nm, 47.65, 47.45 at 546 nm, 48.5, 48.2 at 589 nm and 49.5, 49.0 at 650 nm. Seven electron probe micro-analyses of vymazalováite give an average composition: Pd 40.42, Bi 49.15, Ag 0.55, Pb 1.02, S 7.77 and Se 0.26, total 99.17 wt.%, corresponding to the empirical formula Pd3.05(Bi1.89Ag0.04Pb0.04)Σ1.97(S1.95Se0.03)Σ1.98 based on a total of 7 atoms per formula unit. The simplified formula is Pd3Bi2S2. The mineral is cubic, space group I213, with a = 8.3097(9) Å, V = 573.79(1) Å3 and Z = 4. The density calculated on the basis of the empirical formula and cell dimensions of synthetic vymazalováite is 9.25 g/cm3. The strongest lines in the powder X-ray diffraction pattern of synthetic vymazalováite [d in Å (I) (hkl)] are: 4.15(32)(200), 2.93(78)(220), 2.40(100)(220), 2.08(53)(400), 1.695(34)(422), 1.468(35)(440) and 1.252(31)(622). The structural identity of natural vymazalováite with synthetic Pd3Bi2S2 was confirmed by electron back-scatter diffraction measurements on the natural sample. This new mineral honours Dr Anna Vymazalová of the Czech Geological Survey, Prague.

Research paper thumbnail of Chadak Gold-Silver Deposit, Uzbekistan: An Example of Fluid Evolution in a Rejuvenated Epithermal System.

There is a small group of volcanic-hosted low-sulfidation gold deposits with an anomalous regime ... more There is a small group of volcanic-hosted low-sulfidation gold deposits with an anomalous regime of fluid evolution, e.g. high temperature jumps after the main stage of epithermal ore deposition. As a result, calc-silicate, skarn-like assemblages are developed after carbonate in quartz-carbonate-adularia gold bearing veins. Most of the deposits are distributed in Mesozoic volcanic terrains in the Russian Far East (Sidorov et al., 1989) as well as in the Chatkal-Kurama late-Paleozoic volcanic terrain (Uzbekistan and Tadjikistan, Central Asia). Among these deposits are the Chadak, Kyzylcheku, Shkol'noe, and Bichanzor gold deposits, and several small occurrences not of commercial importance. As a rule, not all veins contain high temperature calcsilicates (wollastonite, garnet, epidote), but only those located in the most heated parts of deposits, e.g. near an intrusion cupola (Chadak) and/or intramineralization granitoid dikes (Shkol'noe). Few fluid inclusion and related stable isotope studies have examined the details of mineral-forming processes in the deposits.

Drafts by Vladimir Kozlov

Research paper thumbnail of New data on Se-bearing minerals of the tetrahedrite group from Ozernovskoe deposit (Kamchatka, Russia) and some proposed additions to the goldfieldite subgroup

preprint, 2022

Ten mineral species are distinguished among tetrahedrite group minerals in Ozernovskoye Au-Te-Se ... more Ten mineral species are distinguished among tetrahedrite group minerals in Ozernovskoye Au-Te-Se deposit on the base of the new classification scheme for natural tetrahedrite group minerals presented by Biagioni et al., 2020. Based on composition and EBSP patterns indexing two species are apparently new: “bismuthogoldfieldite” and “arsenselenogoldfieldite”. Both are not formally approved by IMA yet. The EBSD data show that both have the same crystal symmetry as other species of the tetrahedrite group (cubic, I-43m (217) space group) but unit cell parameters have yet to be determined. In some rare cases, Ga is presented in Mn-bearing tetrahedrite-(Cu) and tennantite-(Cu) – up to 1.8 wt.% (0.43 apfu.). No gallium has been previously reported in this mineral at these concentration levels (George at al., 2017).

Research paper thumbnail of Vymazalováite, Pd3Bi2S2 , a new mineral from the Noril'sk -Talnakh deposit, Krasnoyarskiy region, Russia 2 3

Mineralogical Magazine (2018) 82 (2): 367–373, 2018

Vymazalováite, Pd3Bi2S2 is a new platinum-group mineral discovered in the Komsomolsky mine of the... more Vymazalováite, Pd3Bi2S2 is a new platinum-group mineral discovered in the Komsomolsky mine of the Talnakh deposit, Noril’sk district, Russia. It forms small (from a few μm to 20–35 µm) inclusions or euhedral grains in intergrowths of polarite, sobolevskite, acanthite and unnamed (Pd,Ag)5BiS2 in aggregates (up to ~200 µm) in galena and rarely in chalcopyrite. It occurs with telargpalite, cooperite, braggite, vysotskite, sopcheite, stibiopalladinite, sobolevskite, moncheite, kotulskite, malyshevite, insizwaite, Au-bearing silver and the newly described mineral kravtsovite (PdAg2S) in association with pyrite, chalcopyrite and galena in vein-disseminated mineralization in skarn rocks. Synthetic vymazalováite is brittle; it has a metallic lustre and a grey streak. In plane-polarized reflected light, vymazalováite is creamy grey and appears slightly brownish against galena in the assemblage with chalcopyrite. It exhibits no internal reflections. Average reflectance values in air for natural and synthetic vymazalováite are (R natural, R synthetic in %) are: 46.35, 45.7 at 470 nm, 47.65, 47.45 at 546 nm, 48.5, 48.2 at 589 nm and 49.5, 49.0 at 650 nm. Seven electron probe micro-analyses of vymazalováite give an average composition: Pd 40.42, Bi 49.15, Ag 0.55, Pb 1.02, S 7.77 and Se 0.26, total 99.17 wt.%, corresponding to the empirical formula Pd3.05(Bi1.89Ag0.04Pb0.04)Σ1.97(S1.95Se0.03)Σ1.98 based on a total of 7 atoms per formula unit. The simplified formula is Pd3Bi2S2. The mineral is cubic, space group I213, with a = 8.3097(9) Å, V = 573.79(1) Å3 and Z = 4. The density calculated on the basis of the empirical formula and cell dimensions of synthetic vymazalováite is 9.25 g/cm3. The strongest lines in the powder X-ray diffraction pattern of synthetic vymazalováite [d in Å (I) (hkl)] are: 4.15(32)(200), 2.93(78)(220), 2.40(100)(220), 2.08(53)(400), 1.695(34)(422), 1.468(35)(440) and 1.252(31)(622). The structural identity of natural vymazalováite with synthetic Pd3Bi2S2 was confirmed by electron back-scatter diffraction measurements on the natural sample. This new mineral honours Dr Anna Vymazalová of the Czech Geological Survey, Prague.

Research paper thumbnail of Chadak Gold-Silver Deposit, Uzbekistan: An Example of Fluid Evolution in a Rejuvenated Epithermal System.

There is a small group of volcanic-hosted low-sulfidation gold deposits with an anomalous regime ... more There is a small group of volcanic-hosted low-sulfidation gold deposits with an anomalous regime of fluid evolution, e.g. high temperature jumps after the main stage of epithermal ore deposition. As a result, calc-silicate, skarn-like assemblages are developed after carbonate in quartz-carbonate-adularia gold bearing veins. Most of the deposits are distributed in Mesozoic volcanic terrains in the Russian Far East (Sidorov et al., 1989) as well as in the Chatkal-Kurama late-Paleozoic volcanic terrain (Uzbekistan and Tadjikistan, Central Asia). Among these deposits are the Chadak, Kyzylcheku, Shkol'noe, and Bichanzor gold deposits, and several small occurrences not of commercial importance. As a rule, not all veins contain high temperature calcsilicates (wollastonite, garnet, epidote), but only those located in the most heated parts of deposits, e.g. near an intrusion cupola (Chadak) and/or intramineralization granitoid dikes (Shkol'noe). Few fluid inclusion and related stable isotope studies have examined the details of mineral-forming processes in the deposits.

Research paper thumbnail of New data on Se-bearing minerals of the tetrahedrite group from Ozernovskoe deposit (Kamchatka, Russia) and some proposed additions to the goldfieldite subgroup

preprint, 2022

Ten mineral species are distinguished among tetrahedrite group minerals in Ozernovskoye Au-Te-Se ... more Ten mineral species are distinguished among tetrahedrite group minerals in Ozernovskoye Au-Te-Se deposit on the base of the new classification scheme for natural tetrahedrite group minerals presented by Biagioni et al., 2020. Based on composition and EBSP patterns indexing two species are apparently new: “bismuthogoldfieldite” and “arsenselenogoldfieldite”. Both are not formally approved by IMA yet. The EBSD data show that both have the same crystal symmetry as other species of the tetrahedrite group (cubic, I-43m (217) space group) but unit cell parameters have yet to be determined. In some rare cases, Ga is presented in Mn-bearing tetrahedrite-(Cu) and tennantite-(Cu) – up to 1.8 wt.% (0.43 apfu.). No gallium has been previously reported in this mineral at these concentration levels (George at al., 2017).