Chlorite

The Kletno deposit in the Śnieżnik Massif (Central Sudetes, SW Poland), mined for Fe, U, Ag, Cu, fluorite, and marble through the ages, developed at the contact of marbles and orthogneiss. Here, we present a new Fe-Ti-V-ore (containing up to 14.07 wt.% Fe, 2.05 wt.% Ti, and 2055 ppm V in bulk rock) and ornamental- to gem-quality talc prospect at the southwest margin of this deposit. This newly documented Fe-Ti-V mineralization is hosted in hornblendites, dolomite veins, and chlorite schists, which, along with talc, envelopes a tectonic slice of serpentinite. Hornblendites are interpreted as metamorphosed ferrogabbros, derived from the same mafic melts as adjacent barren metagabbros. The oxygen and carbon isotope compositions of metabasites and dolomite veins (amphibole δ18O values = 8.8-9.3‰; carbonate δ18O values = 12.8-16.0‰, and δ13C values = −8.3‰ to −7.2‰), in combination with those of the country marbles (carbonate δ18O and δ13C values = 23.2‰ and +0.1‰, respectively), suggest that mineralization-bearing hornblendites formed due to interaction of the mafic magma with CO2 released during the decarbonation of the sediments. The CO2-bearing fluid interaction with gabbros likely caused carbonation of the gabbros and formation of the dolomite veins, whereas talc formed due to Si-rich fluids, possibly derived from a mafic intrusion, interaction with serpentinite, or due to the metasomatism of the serpentinite-gabbro assemblage. Moreover, fluids leaching Fe and Ti from the adjacent sediments can mix with the mafic magma causing enrichment of the magma in Fe and Ti. Consequently, the mineralization-bearing ferrogabbros became even more enriched in Fe and Ti, which can be linked with the formation of Fe-Ti-V ore bodies.

20.5.2008 Monthermé………………………………………………………………….. 2
Revin …………………………………………………………………….…. 4
Rocroi ………………………………………………………………………. 5
Fepin ………………………………………………………………….…….. 5
Quarry von Vireux ………………………….……………………………… 6
Le Mur de Vireux-Molheim …………………………………..……………. 7

The Kletno deposit in the Śnieżnik Massif (Central Sudetes, SW Poland), mined for Fe, U, Ag, Cu, fluorite, and marble through the ages, developed at the contact of marbles and orthogneiss. Here, we present a new Fe-Ti-V-ore (containing up to 14.07 wt.% Fe, 2.05 wt.% Ti, and 2055 ppm V in bulk rock) and ornamental- to gem-quality talc prospect at the southwest margin of this deposit. This newly documented Fe-Ti-V mineralization is hosted in hornblendites, dolomite veins, and chlorite schists, which, along with talc, envelopes a tectonic slice of serpentinite. Hornblendites are interpreted as metamorphosed ferrogabbros, derived from the same mafic melts as adjacent barren metagabbros. The oxygen and carbon isotope compositions of metabasites and dolomite veins (amphibole δ18O values = 8.8–9.3‰; carbonate δ18O values = 12.8–16.0‰, and δ13C values = −8.3‰ to −7.2‰), in combination with those of the country marbles (carbonate δ18O and δ13C values = 23.2‰ and +0.1‰, respectively), suggest...

Quartz veins hosted in the infra and overlying series to the (Sardic) Upper Ordovician Unconformity provide new insights into the structural and thermal evolution of the pre-Variscan rocks of the Eastern Pyrenees. In the La Molina area (Canigó massif), two generations of metric-scale quartz veins (V1 and V2) are distinguished by their distribution patterns and their relationship with deformational macro, meso, and microstructures. P-T formation conditions are obtained by combining chlorite geothermometry and fluid inclusion microthermometry data.
Discrepancies on formation temperature for chlorites located at different positions within the veins are discussed, concluding that veins grew in a low fluid/rock ratio regime. V1 veins can be related to the Late Ordovician
synsedimentary faulting episode as revealed by their distribution patterns, formation mechanisms, and fluid-rock interactions. We propose an Alpine age for the V2 veins, based on their structure and the emplacement conditions of 318±12°C and 2.4±0.2kbar, with an estimated geothermal gradient of 34°C∙km-1 and a burial depth of ca. 9km. Results obtained here are compared with other quartz veins spread throughout the Palaeozoic basement of the Eastern Pyrenees.