Prosser molded beads were made in France and Bohemia from the 1860s to the 1970s for trade in Africa and North America. Extensive sales and distribution networks were created by the Bapterosses (France) and Redlhammer (Bohemia) companies to both continents. Their innovative manufacture makes them visually and chemically distinct. In this study, 175 Prosser molded beads found in an archaeological context in south-central Oregon were examined with XRF. The purpose of the study is to determine if elemental analysis can be used to understand where and when Prosser molded beads were manufactured. Three groups of elements that are chemically related, either naturally or by deliberate addition, were examined to identify which of them showed statistically significant variation in the composition. Results show chemical variation between beads of the same color that fall into at least two distinct production groups.