The one-carat diamond price index fell 0.9% month-on-month in September, down 5.4% from a year earlier and 3.6% below the level since the beginning of 2025. The data was cited by industry agency Rapaport, which calculates the international diamond price index.
The situation with US tariffs and the sale of De Beers have created uncertainty in the market, Rapaport noted. Independent jewelry companies in the US showed solid retail sales in anticipation of the peak season. However, the imposed import tariffs have made it difficult for foreign suppliers to operate in the important US retail market. Stocks have begun to move to the US in anticipation of the new tariffs, which come into effect on August 7. On September 5, the White House added diamonds to the list of possible exemptions for countries that have reached trade agreements with the United States.
The 0.3-carat polished diamond price index fell 6% month-on-month in September and 0.2% compared to September last year, and is down 2.2% since the beginning of 2025. The 0.5-carat polished diamond price index fell 6% in September and 14.2% year-to-date. The 3-carat polished diamond price index was unchanged in September and down 1% year-to-date.