The gemstones entered the market earlier this year following initial reports and social media coverage. An earlier investigation by the Swiss Gemmological Institute (SSEF) found that Ethiopian gemstones closely resembled those from established sources, particularly Brazil, making their geographic origin difficult to determine.
Gübelin Gem Lab began research in May after detecting a chemical composition that differed from its reference data for Brazil, Mozambique, and Nigeria. The laboratory collected around 300 rough and faceted gemstones.
Additionally, the Gemological Institute of America (GIA) began its investigation in June and examined more than 100 gemstones sourced from the Ferreira Group in July.
Both laboratories concluded that the material is a new Ethiopian source of copper-bearing tourmaline that meets the accepted definition of Paraíba tourmaline.
The Ethiopian gemstones have a distinct chemical profile that differentiates them from Paraíba tourmaline found elsewhere and range from blue and bluish green to violet and purple. Some rough specimens are colourless, while many display pronounced colour zoning.
GIA and Gübelin confirmed they will continue to study Ethiopian material as new samples become available. Reports of their gemmological, spectroscopic, and chemical analyses have been slated for an upcoming issue of Gems & Gemology.
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