Nordenskiöldine CaSnB₂O₆ from the locality Kozlov near Nedvědice, new rare accessoric mineral for Nedvědice marblesArticle PDF
Nordenskiöldine CaSnB₂O₆ from the locality Kozlov near Nedvědice, new rare accessoric mineral for Nedvědice marbles
Very rare mineral of Europe – nordenskiöldine CaSnB2O6 – was found in Sn-rich calc-silicate assemblage (tin skarn) of Nedvědice marbles near Kozlov (4 km N from Nedvědice, western Moravia). It forms rare euhedral grains approx. 3–10 μm in size enclosed in calcite. Nordenskiöldine was identified using an electron microprobe, its chemical composition (Ca0.965–1.020 Mg0.003–0.007 Fe0.005 Mn0–0.003) Sn0.990–1.013 (B2 F0–0.039) O6 corresponds to the theoretical formula. Besides calcite the mineral assemblage contains vesuvianite, Sn-andradite, malayaite, fluorapatite, cassiterite and stokesite. Nordenskiöldine crystallized as primary Sn-B skarn mineral under conditions enriched especially in B2O3 and poor in SiO2 and CO2.