gsminmag Mineralogical Magazine Mineralogical Magazine 0026-461X Mineralogical Society 10.1180/minmag.1990.054.376.05 Silicate Mineralogy Genthelvite and Willemite, Zinc Minerals Associated with Alkaline Magmatism from the Motzfeldt Centre, South Greenland Finch Adrian A. Grant Institute of Geology, West Mains Road, Edinburgh EH9 3JW, UK 9 1990 54 376 407 412 Copyright © 1990, The Mineralogical Society 1990 Abstract

Two new occurrences of Zn-rich minerals are described from the SM6 lujavrite unit of the Motzfeldt alkaline centre, South Greenland. Zinc and beryllium complexes in the magma gave rise to the formation of interstitial grains of genthelvite (Zn4Be3Si3O12S), identified in samples by strong green cathodoluminescence. It is suggested that subsequent metasomatism leached Be from the genthelvite, giving rise to the formation of associated willemite (Zn2SiO4).

 Keywords willemite genthelvite metasomatism Igaliko Greenland