Aquamarine beryl from Zealand station, Canada: A mineralogical and stable isotope study

Abstract

Aquamarine crystals occur in crustal A-type pegmatite-aplite dykes and associated quartz veins and greisen zones at the Zealand Station Be-Mo deposit, south-central New Brunswick (Canada). Electron-probe microanalysis (EPMA) of aquamarine determined that the chromophore Fe (< 1.4 wt. % FeOT) is present in octahedral sites, with substitutions responsible for simple and oscillatory zonation (SEM-BSE imaging). Average water content (1.53 wt. %) was calculated using an empirical formula, consistent with two TREL (>800 °C) of 1.3-1.4 wt. % in beryl channels. The δ18O of the quartz and beryl were within 1 ‰, consistent with magmatic crystallization from an 18O enriched source, and δD values on channel water have magmatic signatures.