What to Call a Diamond

Solitaire International: A growing debate over terminology is reshaping how the trade defines and differentiates synthetics from natural diamonds.

Heated exchanges at the CIBJO Congress in Paris, along with France’s reaffirmation of the term “synthetic,” have brought language back to the center of the discussion after years in which the word became largely taboo.

That shift, reinforced by the Gemological Institute of America’s move away from the 4Cs in its color and clarity assessments for lab-grown diamonds, points to a broader reassessment of how synthetics are positioned in the market.

Falling wholesale and retail prices have only sharpened the issue, as inconsistent language risks masking widening differences in value, origin, and market behavior. With consumer confidence on the line, what the industry chooses to call a diamond is fast becoming one of its most consequential debates heading into 2026 and beyond.

I explore these themes in my December column for Solitaire International: What to Call a Diamond

Image: Diamond carbon seeds used in the growth process for synthetic diamonds. (De Beers)