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Color origin is an important part of pearl identification for gemological laboratories. Freshwater cultured pearls can exhibit a wide range of colors, which can be either naturally formed or artificially modified by post-harvest treatments. The most common color treatments are dyeing and irradiation. In this project, a group of 23 freshwater "Edison" pearls (a trade name referring to near-round to round freshwater bead cultured pearls invented and produced by Zhejiang Grace Pearl Jewellery Co Ltd in China), reportedly with a mix of natural and treated colors, were analyzed using various gemological and advanced instrumental techniques in order to distinguish their color origin. A number of techniques, including microscopic observation, long-wave UV fluorescence observation, long-wave and short-wave fluorescence spectroscopy, Raman spectroscopy, and trace element analyses, were used in this study. Of the 23 freshwater samples, 19 have been confirmed as bead cultured pearls and 4 have been identified as non-bead cultured pearls. In addition, seven samples have been identified as colortreated, while five of the remaining 16 samples were also identified as being optically brightened (a process commonly used on freshwater cultured pearls to improve appearance factors such as luster). Our results proved that color treatment in these freshwater pearls could be confidently identified using this combination of techniques, as could optical brightening processes that are routinely applied to untreated, naturally colored freshwater cultured pearls post-harvest.