Vörös A. szerk.: Fragmenta Mineralogica Et Palaentologica 11. 1983. (Budapest, 1983)

33 fi ß Kas S2\ 31 V V ..... — Fig. 5 Chemical zoning across 3 different garnet crystals from the Tóbércbánya albite granite. A; Tb-8/3, B; Tb-8/5, C: Tb-8/2. Continuous lines: Ca, doted lines: Mn, dashed lines: Mg, dash and dot lines: Fe occurrence of garnet in andesitic, dacitic and rhyolitic rocks of continental plate margins can be interpreted as an argument in favour of the xenocrystal origin, however the fact may also be explained in case the garnet were cognate (see below). In contrast, the locally widespread occurrence of relatively euhedral garnet megacrysts speaks rather for a high pressure cognate origin (GILL 1981). The slight chemical differences among the garnet-bearing acid andésites of Hungary do not enable us to relate the chemistry of garnets to that of the host rock. Nevertheless Mg/Fe was demonstrated to be markedly higher in garnets from andésites than in those from dacites (OLIVER 1956, FITTON 1972, BROUSSE & al. 1972). In addition, minor elements such as Y, La, Sc, V and Cr differ