Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-28T15:34:36.506Z Has data issue: false hasContentIssue false
  • English
  • Français

Two morphologies of pyrophanite in Mn-rich assemblages, Gangpur Group, India

Published online by Cambridge University Press:  05 July 2018

B. R. Nayak  and
B. K. Mohapatra
B. R. Nayak
Affiliation:
Regional Research Laboratory, Bhubaneswar - 751 013, Orissa, India
B. K. Mohapatra
Affiliation:
Regional Research Laboratory, Bhubaneswar - 751 013, Orissa, India
Get access Rights & Permissions [Opens in a new window]

Abstract

Pyrophanite is widely distributed in metamorphic Mn-rich rock assemblages of the Gangpur Group, India. It occurs in two distinct habits: as an independent phase, and as an exsolved phase within hematite. The well developed large sized crystals coexist with spessartine in Mn-silicate facies rocks. In contrast, the exsolved crystals occur as fine needle/bleb-like crystallites intergrown with hematite in Mn-silicate-oxide facies rocks. Compositionally the exsolved crystals are enriched in iron, present in both the ferric and ferrous states. The two morphologies of pyrophanite attest to their formation under different environmental conditions. The independent pyrophanite is formed from a Mn-Ti rich precursor under low oxygen fugacity conditions while the hematite-pyrophanite intergrowth evolved from an Fe-Mn-Ti rich precursor under higher fO2 conditions.

Keywords

pyrophanitemanganese depositshematiteGangpur GroupIndia
Type
Research Article
Information
Mineralogical Magazine , Volume 62 , Issue 6 , December 1998 , pp. 847 - 856
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Andersen, D.J. (1988) Internally consistent solution models for Fe-Mg-Mn-Ti oxides. PhD dissertation, State University of New York at Stony Brook, xii + 202 pp.Google Scholar
Craig, J.R., Sandhaus, D.J. and Guy, R.E. (1985) Pyrophanite MnTiO3 from Sterling Hill, New Jersey. Canad. Mineral., 23, 491–4.Google Scholar
Craig, J.R. and Vaughan, D.J. (1981) Ore Microscopy and Ore Petrography. John Wiley and Sons, New York. 406 pp.Google Scholar
Dasgupta, S., Fukuoka, M. and Roy, S. (1984) Hematite-pyrophanite intergrowth in gondite, Chikla area, Sausar Group, India. Mineral. Mag., 48, 558–60.CrossRefGoogle Scholar
Fermor, L.L. (1909) The manganese ore deposits of India. Mem., Geol. Surv. India, 37, 610 pp.Google Scholar
Haggerty, S.E. (1976) Opaque mineral oxides in terrestrial igneous rocks. In Oxide Minerals (Rumble, D. III, ed.). Min. Soc. Amer. (Rev. Mineral). 3, 101–300.Google Scholar
Lindsley, D.H. (1981) In Reviews in Mineralogy, 3, (Rumble, D. III, ed.), Min. Soc. Amer., 1–39.Google Scholar
Lindsley, D.H. (1991) Experimental studies of oxide minerals. In Reviews in Mineralogy, 25, (Lindsley, D.H., ed.), Min. Soc. Amer., p. 93.Google Scholar
Mucke, A. and Oakes, M. (1986) Pyrophanite: a typical mineral in the Pan-African Province of Western and Central Nigeria. J. Afric. Earth Sci., 5, 675–89.Google Scholar
Nayak, B.R., Mohapatra, B.K. and Sahoo, R.K. (1997) Metamorphic Mn-rich assemblages from Gangpur Group of rocks, Orissa. Vistas in Geological Research, Utkal Univ. Spl. Publ. no. 2, 137–48.Google Scholar
Nicholson, K., Nayak, V.K. and Nanda, J.K. (1994) Manganese ores of the Goriajhor-Monmunda area, Sundergarh district, Orissa, India. In Manganese Mineralization, Abstract volume, Geol. Soc. London.Google Scholar
Palache, C., Berman, H. and Frondel, C. (1944) Dana's System of Mineralogy, 7th Edn., Vol. 1, 834 pp.Google Scholar
Ramdohr, P. (1969) The Ore Minerals and their Intergrowths. Pergamon, London, 1174 pp.Google Scholar
Rao, D.S., Acharya, B.C. and Sahoo, R.K. (1994) Pyrophanite from Nishikhal manganese deposit, Orissa. J. Geol. Soc. India, 44, 91–3.Google Scholar
Roy, S. (1966) Syngenetic manganese formations of India. Jadavpur University Publication, Calcutta, 219 pp.Google Scholar
Roy, S. (1981) Manganese Deposits. Academic Press, London, 457 pp.Google Scholar
Sivaprakash, C. (1980) Mineralogy of manganese deposits of Koduru and Garbham, Andhra Pradesh, India. Econ. Geol., 75, 1083–104CrossRefGoogle Scholar
Zak, L. (1971) Pyrophanite from Chvaletice (Bohemia). Mineral. Mag., 38, 312–6CrossRefGoogle Scholar