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The Meliata unit, situated in the SE part of the Western Carpathians, represents an accretionary complex assembled during the closure of the Triassic-Jurassic Meliata oceanic basin. Blueschists, ophiolites and very low-grade metamorphosed sedimentary rocks are imbricated in a tectonic zone between the Gemericum and the Silica nappe. Petrological and microstructural analyses indicate a single progressive deformation coincident with prograde metamorphism at blueschist facies conditions. The foliation is defined by preferred orientation of mica, blue amphibole and rarely also by Na-pyroxene. The exhumation path is documented by ductite deformation, formed at blueschist-greenschist facies boundary and at greenschist facies conditions. The E-W directed thrust faults which are parallel to the foliation seem to be responsible for exhumation of the blueschists. Later stages of deformation in phyllites are documented by shear bands that crosscut the blueschist facies foliation. Low-temperature Cretaceous nappe tectonics resulted in brittle deformation and used mostly the older tectonic systems that formed at blueschist-greenschist facies conditions

Meliata blueschists originated from basalts, limestones, pelites, psammitic and amphibolite facies basement rocks. Compositionally, the metabasalts have a geochemical signature mostly indicative of a transitional arc-MORB origin, but some mafic rocks having affinity with within plate basalts also present. The mafic blueschists consist of blue amphibole, epidote and albite, rarely also garnet, Na-pyroxene and chloritoid. Apart from phengite and quartz the metapelites and metapsammites contain one or more of the minerals: chloritoid, paragonite, glaucophane, albite, chlorite, occasionally also Na-pyroxene and garnet. Amphibolite facies rocks contain relic garnet, plagioclase and hornblende, the latter two replaced by albite and blue amphibole, respectively. The zoning patterns of blue amphibole, garnet and chloritoid suggest their formation during prograde stage of metamorphism. P-T conditions of meta-morphism are estimated to be about 350-460 oC and 10-12 kbar.

This work focuses on first occurrences of more than 20 silicate minerals in the study area. In addition to amphiboles group (six minerals), pyroxenes (three minerals), different varieties of garnets and schist silicates and some Mn-rich minerals are described in this paper. Several of these minerals have not been known in the Western Carpathians yet. The studied minerals come from greenschist facies sequences of the Early Paleozoic of the Gemericum and from blueschists of the Meliata unit.