This article describes the first application of laser-induced breakdown spectroscopy (LIBS) to gemology. So far, the detection of Be-diffused sapphire and ruby has been based on LA-ICPMS or SIMS, neither of which is readily available to most laboratories. In this study, we use LIBS to detect beryllium in corundum at very low concentrations (down to ~2 ppm). This technique is a reliable tool for identifying Be diffusion–treated sapphires, and is affordable for most commercial gemological laboratories. As with other laser-based techniques, LIBS may cause slight damage to a gemstone, but this can be minimized by choosing appropriate instrument parameters.