57^{57}Fe Mössbauer Spectroscopy on Two Romanian Carpathian Pumpellyites

The authors obtained the Fe$^{57}$ Mössbauer spectra of two pumpellyite samples obtained from two different mineral sources in the Romanian Carpathians. Using a specialized computation program of the quadrupole splitting spectral parameter, QSCOMP, the observed quadrupole doublets were attributed to the ferric and ferrous ions in octahedral sites. The refined analysis of spectral parameters permitted us to characterize both the oxidation state, the electronic configuration and the coordination symmetry with the distortions and occupancies of pumpellyite constituting iron ions. The differences of the spectral parameters giving the data of the iron abundance, the chemical iron-oxygen bonds, the deformation and occupancies of iron octahedra, observed at the two studied samples, are discussed and correlated by the different genesis conditions of two pumpellyite-bearing occurrences

Badania, ocena i zarządzanie zasobami trawertynu ze złóż Banpotoc-Carpinis (South Apuseni Mts., Rumunia)

Romania is not a large country but, due to the very complex geological structure, it has 110 mineral and power substances with identified and quantified resources and reserves. In time, the most numerous from these (82) have been exploited at the ground surface, in over 3,492 identified quarries and open pits. Travertine has been exploited since ancient times in Romania the exploitation of Brezinta (Mehedinti county) has been known since the Roman times. Although resources are found in many other zones, only two travertine deposits are presently exploited by Marmosim S.A.: Banpotoc-Carpinis and Geoagiu. Travertine extraction began at the Banpotoc-Carpinis deposit in 1870 and 9 quarries have functioned during time from which only one is still active today. This paper presents the way in which the research and valuation of the deposit was made, how the exploitation and processing of the travertine is made nowadays and what are its uses.Rumunia nie jest dużym krajem, ale ze względu na bardzo złożoną strukturę geologiczną posiada 110 surowców mineralnych o określonych zasobach. Najwięcej z nich (82) jest eksploatowanych odkrywkowo w ponad 3449 kamieniołomach i odkrywkach. Trawertyn był eksploatowany w Rumunii od czasów starożytnych. Eksploatacja w Brezinta (powiat Mehedinti) jest znana od czasów rzymskich. Chociaż zasoby trawertynu znajdują się w wielu innych rejonach kraju, to tylko dwa złoża trawertynu są obecnie eksploatowane przez Marmosim S.A .: Banpotoc-Carpinis i Geoagiu. Wydobycie trawertynu ze złoża Banpotoc-Carpinis rozpoczęło się w 1870 r. w 9 kamieniołomach, z których obecnie funkcjonuje tylko jeden. W artykule przedstawiono sposób, w jaki przeprowadzono badania i wycenę złoża trawertynu, jego eksploatację i przeróbkę oraz zastosowanie

Replacement and authigenic mineralogy of metal contaminants in stream and estuarine sediments at Newtownards, Northern Ireland.

Tidal mudflats are locally enriched in heavy metals at the head of Strangford Lough in Northern Ireland, where drainage from the hinterland enters the sea lough via a tidal canal in an urban area. To characterize the metallic contaminants and investigate their provenance, heavy particles separated from stream, canal and estuarine sediments were analysed by electron microprobe and laser Raman microspectroscopic methods. Potential metal sources are mineralization in the catchment area and industrial or domestic pollution. Anthropogenic particles include metallic grains, alloys and compounds of Pb, Zn, Cu, Fe, Cr and Sn. Alteration of metallic particles includes de-zincification of brass in freshwater sediment and replacement of Cu wire by covellite in brackish to marine sediment. Mobility of Cu, Fe and S in canal and estuarine sediments is indicated by the authigenic growth of framboidal Fe sulphide on oxide substrates and of chalcopyrite rims on covellite. Intricate colloform and platy crystalline textures suggest a cyclical deposition of covellite and chalcopyrite under conditions of varying redox and salinity. Lead and Cr mobility in the contaminated estuarine sediment is shown by the authigenic formation on Pb-rich substrates of heterogeneous Pb- and Cr-rich sulphate-phosphate compounds and Pb-oxychlorides