Previous analyses of the elemental composition of white glass beads have shown that the opacifier used during glass manufacture is temporally diagnostic, with a transition from tin to antimony to arsenic to fluorine. To date, most researchers using this fact for chronological purposes have focused on British, Dutch, and French contact sites in the northeastern United States and Canada. Many of these studies have relied on expensive, and sometimes minimally destructive, techniques. X-ray fluorescence spectrometry is a widely available, non-destructive technique that can be used to identify glass opacifiers extremely rapidly and inexpensively. This technique was used to analyze 783 specimens of four varieties of drawn white glass beads from burial contexts at Mission Santa Catalina de Guale, Georgia, demonstrating that the “opacifer-dating” method is also applicable to Spanish colonial sites in the southeastern United States.