Referenza:
▪ Ostrooumov, M. & Taran, Yu. (2016): Vanadium, V – a new native element mineral from the Colima volcano, State of Colima (Mexico), and implications for fumarole gas composition. Mineralogical Magazine, 80, 371-382.
Abstract:
Vanadium, V, is a new mineral species that has been found in sublimates (mineral precipitates) of high-temperature fumaroles of Colima volcano in Mexico. This mineral precipitates from the high-temperature volcanic vapor over a narrow temperature range of 550-680°C, and occur in association with other V-bearing minerals: colimaite (K3VS4) and shcherbinaite (V2O5). Native vanadium has been found on the inner wall of a silica tube and subsequently in the rock adjacent to the Z3 fumarole in the natural wall matrix. Vanadium forms smooth, irregular to flattened crystals, 5-20 micron in diameter. Smaller irregular crystals have also been observed in silica tubes. Due to its small crystal size, its physical properties (hardness, cleavage, and density) could not be determined. An EDS spectrum indicated the presence of V, Fe, Al and Ti with the empirical formula calculated on the basis of EPMA analyses: V0.86Fe0.09Al0.04Ti 0.01. The powder-diffraction pattern and a modern single-crystal study were not obtained because of the paucity of natural material. Gandolfi and glancing-angle X-ray diffraction data showed that the microcrystals were of the body-centered cubic phase with space group Im-3m, a = 3.022(3) Å, V=27.60 (5) Å3, and Z=2. The five strongest calculated diffraction lines from this natural compound are [d spacings in Å, (I) (hkl)]: 2.1411 (100), 1.5126 (12)(200), 1.2301 (19)( 211), 0.9565 (8)(310), and 8.8090 (11)(321). The calculated density (Z=2) is 6.033 g/cm-3. Thermochemical modelling was used to explain why very oxidized gas at Colima does precipitate V-minerals and some native elements (vanadium and gold). Vanadium, V, is the second newly recognized mineral species (after colimaite) that was collected from an active fumarole in this volcanic crater. The mineral and the mineral’s name (vanadium) have been approved by the CNMNC (Commission on New Minerals, Nomenclature and Classification) of International Mineralogical Association (IMA # 2012-021a).
▪ Ostrooumov, M. & Taran, Yu. (2016): Vanadium, V – a new native element mineral from the Colima volcano, State of Colima (Mexico), and implications for fumarole gas composition. Mineralogical Magazine, 80, 371-382.
Abstract:
Vanadium, V, is a new mineral species that has been found in sublimates (mineral precipitates) of high-temperature fumaroles of Colima volcano in Mexico. This mineral precipitates from the high-temperature volcanic vapor over a narrow temperature range of 550-680°C, and occur in association with other V-bearing minerals: colimaite (K3VS4) and shcherbinaite (V2O5). Native vanadium has been found on the inner wall of a silica tube and subsequently in the rock adjacent to the Z3 fumarole in the natural wall matrix. Vanadium forms smooth, irregular to flattened crystals, 5-20 micron in diameter. Smaller irregular crystals have also been observed in silica tubes. Due to its small crystal size, its physical properties (hardness, cleavage, and density) could not be determined. An EDS spectrum indicated the presence of V, Fe, Al and Ti with the empirical formula calculated on the basis of EPMA analyses: V0.86Fe0.09Al0.04Ti 0.01. The powder-diffraction pattern and a modern single-crystal study were not obtained because of the paucity of natural material. Gandolfi and glancing-angle X-ray diffraction data showed that the microcrystals were of the body-centered cubic phase with space group Im-3m, a = 3.022(3) Å, V=27.60 (5) Å3, and Z=2. The five strongest calculated diffraction lines from this natural compound are [d spacings in Å, (I) (hkl)]: 2.1411 (100), 1.5126 (12)(200), 1.2301 (19)( 211), 0.9565 (8)(310), and 8.8090 (11)(321). The calculated density (Z=2) is 6.033 g/cm-3. Thermochemical modelling was used to explain why very oxidized gas at Colima does precipitate V-minerals and some native elements (vanadium and gold). Vanadium, V, is the second newly recognized mineral species (after colimaite) that was collected from an active fumarole in this volcanic crater. The mineral and the mineral’s name (vanadium) have been approved by the CNMNC (Commission on New Minerals, Nomenclature and Classification) of International Mineralogical Association (IMA # 2012-021a).