Bagiński, Bogusław and MacDonald, Raymond and White, John C. and Jezak, Lidia (2018) Tuhualite in a peralkaline rhyolite ignimbrite from Pantelleria, Italy. European Journal of Mineralogy, 30 (2). pp. 367-373. ISSN 0935-1221
Full text not available from this repository.Abstract
An occurrence of the rare mineral tuhualite (NaFe3+Fe2+Si6O15) is reported in a peralkaline rhyolitic ignimbrite from the island of Pantelleria, Italy. The mineral formed during devitrification of glassy fiamme and varies in form from anhedral plates to perfectly euhedral in open vesicles. There is significant replacement of Fe2+ by Mn (≤0.37 atoms per formula unit (apfu)) and Zn (≤0.11 apfu), and of Na by K (≤0.13 apfu). The tuhualite possibly formed at temperatures <580 °C at fO2>FMQ in the presence of a hydrous fluid.