"Edison" is a trade name for a new generation of Chinese freshwater cultured pearls that are shell-bead nucleated — a technique traditionally reserved for saltwater varieties. This advanced culturing method produces large, near-round to perfectly round pearls (often 10mm–15mm or larger) with a rich, metallic luster and a broad spectrum of natural colors including deep purples, bronzes, warm pinks, and coppers.
In a landmark study published in the Summer 2021 issue of Gems & Gemology — the peer-reviewed journal of the Gemological Institute of America — GIA researchers analyzed Edison pearls to develop reliable methods for identifying color treatments and optical brightening. The study, titled "Detection of Color Treatment and Optical Brightening in Chinese Freshwater 'Edison' Pearls," demonstrated that a combination of microscopic observation, ultraviolet fluorescence analysis, Raman spectroscopy, and trace-element testing can accurately distinguish natural-color pearls from those that have been artificially enhanced.
What This Means for You
At UnoPearl, we take these findings seriously. We source only freshwater pearls whose color and appearance are verified as natural. We do not use dyed, irradiated, or optically brightened pearls in our jewelry. When you purchase an UnoPearl piece featuring freshwater pearls, you can trust that the color you see is the color nature intended — backed by the same gemological science that the world's leading laboratories rely on.
Reference: Zhou, C., et al. "Detection of Color Treatment and Optical Brightening in Chinese Freshwater 'Edison' Pearls." Gems & Gemology, Summer 2021. Gemological Institute of America.