[en] Geological features of antimony ores are summarized based on previous studies. Stibnite ores and pyrites are major minerals of these ores. Although the ore bodies are diverse in shapes, they are mostly strati form-like and their formation is significantly controlled by their structures. (paper)

[en] Published in summary form only

[en] Abstract only

[en] Microanalytical techniques such as scanning electron microscopy, energy-dispersive x-ray analysis, and electron-beam microprobe analysis have been shown to be ideal for determining the host phases of the minor and trace elements in the Chattanooga shale. Positive correlations were found between pyrite and organic constituents. However, these observations provided no evidence that microorganisms acted as hosts for pyrite framboids. Interestingly, appreciable organic sulfur is still present, suggesting that the sulfur used for the formation of pyrite must have been derived mostly from other sources. It may be that the sulfate-reducing bacteria had an affinity for organic matter and that the organic fragments acted as substrates for pyrite growth

[en] The determination of minor and trace elements in a different geochemical sampling media, pyrite, froM the Bagacay kuroko deposit was done using a combination of nuclear and non-nuclear techniques. The analyzed elements, Cu, V, Pb, Co, Mn and Zn have essentially log-normal distributions. Correlation coefficients were calcUlated to measure the geochemical dependency of the different analyzed elements with Cu and the other elements, except Mn. These close geochemical relationships of V, Pb, Co and Zn with Cu suggest the possible application of these elements as indicators in prospecting for copper-rich deposits in the Philippines using pyrite as the sampling media. (author)

[en] This report is about the geophysical survey carried out in Anomaly II as well as the evidence of the three pyrite mineralization

No abstract available

No abstract available

[en] In present article authors presented the results of some investigationsof acetylene compounds as selectors at flotation of galena, chalcopyrite,antimonite, sphalerite and pyrite

[en] Uranium mineralization hosted by the fluvial channel sandstones of Middle Permian Motur Formation of Satpura Gondwana Basin has been established around Kachhar-Dharangmau area of Betul district, Madhya Pradesh. These channel sandstone are part of the NW trending paleo-channel which defines sedimentation in the sector. The channel is divided into a number of interlacing sub-channels. The sediments of this sector show vertical as well as lateral facies variation resulting into active channel sands and overbanking fines. Seven (7) major sedimentary facies Gt, Gm, St, Sh, Sl and Fm based on grain size, sedimentary structures define the sequence. These facies preserve the signatures of the dynamics of sedimentation that has varied over the geological time. Facies association resultant of the combination of the individual facies, led to identification of the micro-environments consisting of active channel flows, period of waning flow and period of near quiescence.An interplay of these micro-environments has resulted in the formation of porous and permeable host sand lenses, which are principally medium-coarse-gravelly feldspathic sandstone of arenaceous nature and permeability barrier in the form of drapes of mudstone and siltstone. The avulsion of individual channels in spatio-temporal domain has resulted in lensoidal morphology of the host sand lenses.With younger acid intrusives (4-9 ppm U) and felsic volcanics acting as source, the uraniferous solution is envisaged to have followed the permeable path and enriched by oxidative leaching and deposited under anoxic conditions, which is favoured by the presence of sulphide (pyrite) of different generation, carbonaceous matter (organic) and ferrous to ferric oxidation. Uraninite, pitchblende and coffinite has been identified associated with pyrite and carbonaceous matter. Geochemically the major and minor oxide composition of both mineralized and non-mineralized sediments do not show major difference albeit higher concentration of Fe₂O₃, (1.77-19.77%, avg. 5.22%) in the mineralized portion. Trace element composition shows preferential enrichment of V along with U (FO.77 and rZ=0.59). Mo (upto 43ppm) and Se (upto 392ppm) are also concentrated in some portions of the mineralized sandstone. REE distribution suggests enrichment of LREEs over HREEs, indicative of predominantly felsic source for sediments. Sulphur isotopic and ore microscopic study suggests different generations of pyrite,both sedimentary and low temperature hydrothermal (suggested by vein pyrite, probably caused by re-circulation and re-precipitation of sulphide rich solution) and euhedral pyrite (volcanogenic) associated with partly devitrified glassy materials. The migration of uraniferous solutions through these permeable channel sandstones bound by mudstone and finer drapes (barrier for uraniferrous solution) and suitable geochemical interface (reducing agents in the form of sulphides and/or carbonaceous matter) have resulted in mineralization in this sector. (author)