gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1994.058.392.12 Mineralogy Arsenian Nagyagite from Sacarimb, Romania: A Possible New Mineral Species Simon G. Department of Mineralogy, University of Bucharest, l.N.Balcescu Av., 70111 Bucharest, Romania Alderton D. H. M. Department of Geology, Royal Holloway, University of London, Egham, Surrey, TW20 0EX, UK Bleser T. * Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge, CB2 3EQ, UK

Present address: Techn. Universität Clausthal, Inst. f. Mineralogie, Adolph-Roemer Str. 2A, D-38678 Clausthal-Zellerfeld, Germany.

 9 1994 58 392 473 478 6 9 1993 26 11 1993 Copyright © 1994, The Mineralogical Society 1994 Abstract

Arsenic-rich nagyagite (up to 5.5 wt % As) has been discovered in samples from the Au-Ag-Te deposit of Sacarimb, western Romania. Optical properties of the mineral show small but distinct differences to nagyagite (ss). Chemical analyses indicate a substitution of As for Sb, and chemical zonation suggests rapid changes in the chemistry of the mineralising fluids.

 Keywords nagyagite arsenic Sacarimb Romania