Presence of grossular-andradite (grandite) series garnets in nepheline syenite gneiss indicate any carbonate related hydrothermal phenomena?

Dear all, I have nepheline syenite gneisses, consisting of grossular-andradite (grandite) series garnets. Other minerals of these rocks are nepheline (seldom altered), plagioclase, k-feldspar,...

22 January 2023 2,820 11 View