Acta Mineralogica-Petrographica, Abstract Series 1, Szeged, 2003 MINERALS AND MINERAL VARIETIES FROM METAMORPHOSED Mn DEPOSITS OF BISTRITA MOUNTAINS, ROMANIA HÎRTOPANU, P.1 & SCOTT, P.2 1 Geological Institute of Romania, Caransebeş 1, RO-78344 Bucharest, Romania. E-mail:
[email protected] 2 Camborne School of Mines, Redruth, Cornwall, United Kingdom. The Bistrita Mountains belong to the Crystalline Meso- mation of some amphiboles and some pyroxenes into other zoic Zone of the East Carpathians, which consists of super- phases, there are drastical transformations of pyroxenes into posed Variscan and Alpine Nappes, overthrusted eastwards pyroxenoids (johannsenite into rhodonite), pyroxenoids into over the Flysch Zone. The manganese ore is contained by pyroxenoids (pyroxmangite into rhodonite), pyroxmangite Tulghes Group (Tg2 level) of the Variscan Putna Nappe, into manganogrunerite, garnets into garnets (spessartine- situated over the Pietrosu Bistritei Nappe and supporting the calderite into spessartine, spessartine into anisotropic spes- thrusting of the Rebra Nappe. All these Variscan nappes sartine-andradite-grossular), calderite into pyroxmangite- constitute the Alpine Sub-Bucovinian Nappe localised be- magnetite, etc. are the best evidences of continuous variation tween Alpine Infrabucovinian Nappe in the East and the of formation conditions. Alpine Bucovinian Nappe in the West. The Mn ore have a predominant carbonate rather than The mineralogy of Mn metamorphosed deposits from silicate mineralogical composition, which means a great CO2 Bistrita Mts. includes 328 minerals and mineral varieties. fluid control in the carbonation and dehydration processes They may count among the mineralogically the most com- along the many stages of the whole history of the ore and the plex deposits of the world.