Acta Musei Moraviae

Ilmenitite from a soapstone body on the Smrčina Hill near Sobotín

One fragment of ilmenitite was found in heap material coming from a soapstone quarry on the Smrčina Hill near Sobotín in the Jeseníky Mts. The ilmenitite is composed predominatingly of ilmenite (approximately 70 to 80 % by volume), with magnetite, hematite, talc and clinochlore present in minor amounts. The origin of ilmenitite could be explained as the result of fractional crystallization and subsequent density segregation from a Fe-Ti rich magma. This hypothesis is supported by the distinctive higher magnesium content in ilmenite from the ilmenitite (4.4–4.7 wt.% MgO), whereas metamorphogenic ilmenite from soapstone body rocks quarried on the Smrčina Hill has the lower magnesium content (ca. 0.1 wt.% MgO). This is the first finding of ilmenitite in the Silesicum and probably in the entire Bohemian Massif.