S P Deshpande
Articles written in Proceedings – Section A
Volume 49 Issue 3 March 1959 pp 165-173
The paper gives an account of the ore-microscopic study of the manganese ore-minerals collected from Dongribuzurg, Bhandara District, Old M.P. The following are the ore-minerals that have been identified in polished sections: Psilomelane, Pyrolusite, Polianite and Braunite. The characters of these ore-minerals under reflected light are given along with their etch reactions and reflectivity values. In addition, a mineral showing properties different from those shown by any known manganese ore-mineral has been described. The identity of this mineral could only be established on chemical and X-ray studies which are now in progress. Interesting microstructures, like the colloform texture shown by Psilomelane, have been fully described, and the mineral paragenesis based on textural features is given. A note has been added on the origin of Pyrolusite, since the occurrence of large quantities of this mineral in association with highly metamorphosed rocks is curious and interesting.
Volume 51 Issue 4 April 1960 pp 202-218
The paper gives an account of the mineragraphic study of the managanese ore-minerals collected from Satak, Beldongri, Lohdongri and Kachurwahi managanese mines in Nagpur District, Bombay State. The ore-minerals identified in polished sections are Braunite, Sitaparite, Hollandite, Jacobsite, Hausmannite, Manganite, Pyrolusite and Psilomelane. In addition, two unidentified minerals have been fully described and the problem of their nomenclature is discussed. Unusual textural features such as the reaction rim of Braunite between Jacobsite and Pyrolusite and Jacobsite and gangue have been described along with a detailed description of the more common textural features. The mineral paragenesis, based on textural features and physicochemical considerations, has been determined. It is followed by a short discussion on the relationship of the ore-mineral assemblages and the type of metamorphism they have suffered.