Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

B. C. Acharya ¹

Affiliations
1 Mineralogy and Metallography Group, Regional Research Laboratory, Bhubaneswar 751 013, IN

Abstract

No Abstract.

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B. C. Acharya ¹

Affiliations
1 Mineralogy and Metallography Group, Regional Research Laboratory, Bhubaneswar 751 013, IN

Abstract

Sphalerite, galena, chalcopyrite and arsenopyrite are the dominant ore minerals with minor amounts of pyrrhotite, cubanite, marcasite, pyrite and chalcocite. Bornite, stibnite, native bismuth and silver are present in trace quantities. Chemical analyses of the samples reveal variations in different metal values. Sphalerite, galena, chalcopyrite and arsenopyrite are analysed by Scanning Electron Microscope coupled with EDAX analyser to decipher the distribution of valuable elements in them.

The ore needs grinding to 45 microns to liberate 91.70% of galena, 94.49% of sphalerite, 95.31% of chalcopyrite and 98.45% of composite galena-chalcopyrite-sphalerite. This suggests that by physical beneficiation, individual concentrates of Pb, Cu and Zn with good recoveries may be difficult to obtain, but a bulk concentrate of these three metals can be produced.

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B. C. Acharya ¹, D. S. Rao ¹, R. K. Sahoo ¹

Affiliations
1 Regional Research Laboratory, Bhubaneswar 751013, IN

Abstract

Manganese ores of Nishikhal occur as distinctly conformable bands in the khondalite suite of rocks. Presence of phosphorus, iron and silica beyond desirable limit in most of the ores makes them unsuitable for industrial purposes. The dominant ore minerals are psilornelane, cryptomelane, pyrolusite and goethite. These ores are formed by supergene enrichment of primary syngenetic metamorphosed assemblages. Phosphorus is present as a discrete mineral phase in the form of apatite contained in the silicate minerals, as well as fixed in the crystal structure of goethite, cryptomelane and psilomelane. Physical beneficiation may be employed to remove the silicate minerals which will ultimately reduce a part of phosphorus. Removal of iron by this method may be difficult because of the fine grain-size and complex intergrowth with goethite.

Keywords

Economic Geology, Manganese, Koraput, Orissa, Khondalite.

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B. C. Acharya ¹, S. K. Das ¹, R. K. Sahoo ¹, B. C. Patnaik ², N. K. Das ³

Affiliations
1 Regional Research Laboratory, Bhubaneswar 751 013, IN
2 Directorate of Mines, Govt. of Orissa, Bhubaneswar, IN
3 Orissa Remote Sensing Application Centre, Bhubaneswar, IN

Abstract

Tin along with Nb and Ta occurs both as primary mineral in pegmatites and as detrital mineral in the colluvial, eluvial and alluvial placers in Matili-Mundaguda area of Koraput District, Orissa. Cassiterite is commonly associated with soda plagioclase, microcline, perthite, quartz and muscovite, and it invariably contains inclusions of columbite-tantaIite, tapiolite, pyrochlore and fergusonite varying from 0.4 to 18% by volume and 3 to 400 microns in size. Minerals, like ilmenite, magnetite, lepidolite, pyrite, chalcopyrite and sphalerite are also associated with cassiterite. Nb and Ta is present in cassiterite both in solid solution as well as separate mineral phases.

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D. S. Rao ¹, B. C. Acharya ¹, R. K. Sahoo ¹

Affiliations
1 Regional Research Laboratory (CSIR), Bhubaneswar-751013, IN

Abstract

No Abstract.

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B. C. Acharya ¹, B. C. Patnaik ¹

Affiliations
1 Regional Research Laboratory, Bhubaneswar-751013, Orissa, IN

Abstract

In the columbite-bearing pegmatite occurrences in the Eastern Ghats Complex around Talbahal - Karunapali area of Phulbani district, economic concentrations of columbite with appreciable quantities of tungsten and trace of tin are recorded in the colluvial and eluvial placers surrounding the source pegmatite.

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B. K. Nayak ¹, B. C. Acharya ¹, R. K. Sahoo ¹

Affiliations
1 MM Division, Regional Research Lab., Bhubaneswar-751 013, IN

Abstract

Complex system of geochemical variables obtained from manganese ores of Balaghat mine, M.P., is simplified by using R-mode factor analysis of correlation matrix. Eighteen major oxides and trace elemental variable have been expressed in terms of the three common (rotated) factors and genetic interpretations of these factors have been brought out in relation to the manganese deposit.

Keywords

Factor Analysis, Manganese Ore, Balaghat, Madhya Pradesh.

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