Chemical Diffusion in Watermelon Tourmaline : Parallel Versus Perpendicular to C-axis

Abstract

The chemical composition of tourmaline can provide unique insights into the thermal evolution of their growth environment, including that of pegmatites (in igneous systems) and hydrothermal veins (in metamorphic systems). Here, we examine a single crystal of watermelon tourmaline with prominent color variations both perpendicular and parallel to the c-axis. We compare the gradients in chemical contaminants as measured using high-resolution micro-infrared spectroscopy both parallel and perpendicular to the c-axis to determine if the color variation is related to observed abundances in hydroxyl species.