Copper-bearing tourmaline from an East African nation has been authenticated by two leading gemological laboratories, confirming the emergence of a new source for the coveted blue-green gemstone.
Independent labs verify new deposit
Earlier this year, reports of copper-rich gems from the region spread through trade circles. The findings led GIA and Gübelin Gem Lab to conduct separate analyses before releasing their conclusions.
The Swiss laboratory first examined the material in May, detecting a chemical profile that differed from known data for Brazil, Mozambique, or Nigeria. This discrepancy prompted a rapid collection effort.
Over the following weeks, researchers gathered about 300 rough and faceted pieces. The samples came from a private dealer and a field visit by a senior gemologist who worked directly with local merchants near the mining site. The size of the collection enabled detailed testing.
Dr. Peter Tollan, head of research at the lab, stated that despite chemical variation among individual stones, they shared a clear and consistent compositional signature.
U.S. laboratory confirms origin
In June, GIA received parcels labeled as coming from the same source. By July, the Ferreira Group delivered a shipment of over 100 rough and finished stones for study.
Related: Dubai to Host Global Jewellery Fair in October
Dr. Aaron Palke, senior research manager, confirmed the nation could now be identified as an origin on GIA Tourmaline Identification and Origin Reports. The lab documented a range of color for the stones, many displaying pronounced zoning.
Testing revealed copper as the primary color‑causing element, meeting the definition of paraíba tourmaline.
A new mining area can change how this gemstone is sourced, as it has long been tied to only a few locations. Traders and appraisers will use the published data to verify origin and maintain trust in the market.
Both labs plan to expand their reference collections as more specimens become available. Their findings will appear in the next issue of Gems & Gemology, including full gemological, spectroscopic, and chemical results.
Independent research and transparent scientific exchange help establish credibility when a major new deposit enters the market. The work also supports efforts to trace the gem’s journey from mine to consumer.
