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Sapphires related to alkali basalts from the Cerová Highlands, Western Carpathians (southern Slovakia): composition and originBlue, grey-pink and pink sapphires from the Cerová Highlands, Western Carpathians (southern Slovakia) have been studied using CL, LA-ICP-MS, EMPA, and oxygen isotope methods. The sapphire occurs as (1) clastic heavy mineral in the secondary sandy filling of a Pliocene alkali basaltic maar at Hajnáčka, and (2) crystals in a pyroxenebearing syenite/anorthoclasite xenolith of Pleistocene alkali basalt near Gortva. Critical evaluation of compositional diagrams (Fe, Ti, Cr, Ga, Mg contents, Fe/Ti, Cr/Ga, Ga/Mg ratios) suggests a magmatic origin for clastic blue sapphires with lower Cr and Mg, but higher Fe and Ti concentrations in comparison to the grey-pink and pink varietes, as well as similar compositional trends with blue sapphire from the Gortva magmatic xenolith. Moreover, blue sapphires show similar δ18O values: 5.1 ‰ in the Gortva xenolith, 3.8 and 5.85 ‰ in the Hajnáčka placer, closely comparable to mantle to lower crustal magmatic rocks. On the contrary, pink and grey-pink sapphires show higher Cr and Mg, but lower Fe and Ti contents and their composition points to a metamorphic (metasomatic) origin.

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The Ko sice meteorite was observed to fall on 28 February 2010 at 23:25 UT near the city of Ko sice in eastern Slovakia and its mineralogy, petrology, and geochemistry are described. The characteristic features of the meteorite fragments are fan-like, mosaic, lamellar, and granular chondrules, which were up to 1.2 mm in diameter. The fusion crust has a black-gray color with a thickness up to 0.6 mm. The matrix of the meteorite is formed mainly by forsterite (Fo 80.6 ); diopside; enstatite (Fs 16.7 ); albite; troilite; Fe-Ni metals such as iron and taenite; and some augite, chlorapatite, merrillite, chromite, and tetrataenite. Plagioclase-like glass was also identified. Relative uniform chemical composition of basic silicates, partially brecciated textures, as well as skeletal taenite crystals into troilite veinlets suggest monomict breccia formed at conditions of rapid cooling. The Ko sice meteorite is classified as ordinary chondrite of the H5 type which has been slightly weathered, and only short veinlets of Fe hydroxides are present. The textural relationships indicate an S3 degree of shock metamorphism and W0 weathering grade. Some fragments of the meteorite Ko sice are formed by monomict breccia of the petrological type H5. On the basis of REE content, we suggest the Ko sice chondrite is probably from the same parent body as H5 chondrite Mor avka from Czech Republic. Electron-microprobe analysis (EMPA) with focused and defocused electron beam, whole-rock analysis (WRA), inductively coupled plasma mass and optical emission spectroscopy (ICP MS, ICP OES), and calibration-free laser induced breakdown spectroscopy (CF-LIBS) were used to characterize the Ko sice fragments. The results provide further evidence that whole-rock analysis gives the most accurate analyses, but this method is completely destructive. Two other proposed methods are partially destructive (EMPA) or nondestructive (CF-LIBS), but only major and minor elements can be evaluated due to the significantly lower sample consumption.

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