Monthly Update on the Diamond Market - November 2025

Welcome to our monthly overview of the diamond market. Each month, we review key global trends, major developments, and the factors influencing demand, pricing, and commercial strategies. Using reliable sources such as Rapaport News, IDEX, and other specialized industry channels, we aim to provide a clear, accurate, and up to date picture of the market.

General Market Trends

November 2025 saw a market that is becoming more selective and increasingly informed.

• In the United States, the start of the holiday shopping season supported strong demand for high quality diamonds in the 2 to 4 carat range, with particular interest in elongated fancy cuts such as Marquise and Oval.
• In Europe, the market remains uneven. While high net worth buyers continue to favor certified diamonds with transparent origins, the broader industry is still dealing with ongoing geopolitical uncertainty. Conflicts in the Middle East, US EU trade tensions, and trade restrictions involving Russia and Belarus continue to influence the supply of rough diamonds to Europe’s main cutting and polishing centers.
• In Asia, both India and China experienced noticeable slowdowns. Elevated inventory levels remain a key factor, putting pressure on prices across several categories.

Overall, the most important development continues to be a clear market split. Diamonds below 1.20 carats remain under structural pressure, while larger stones have shown greater price stability. The growing focus on certified traceability and distinctive cuts suggests that affluent buyers are becoming more careful, informed, and selective in their purchasing decisions.

Price Trends

In November, diamond prices showed a broadly negative trend, with a clear pattern emerging: sharper declines in lower carat segments and relative stability in higher quality stones.

According to Rapaport, the RapNet Diamond Index (RAPI™) for 1 carat round diamonds (D–H, IF–VS2) fell by 2.6%. Smaller sizes recorded more pronounced declines, with prices down 6% for 0.30 carat stones and 5.1% for 0.50 carat stones. In contrast, 3 carat diamonds posted a slight increase of 0.1%, further highlighting the market’s structural divergence.

The IDEX Polished Price Index confirmed this trend, recording a decline of 1.72%. This drop was steeper than in October (–0.48%), but less severe than in September (–2.08%). High inventory levels across all major markets, combined with growing competition from lab grown diamonds, continue to push sellers of natural stones toward increasingly aggressive discounts.

Overall, November points to a market where quality and rarity remain the only real safeguards of value, while lower quality segments continue to face ongoing structural pressure.

Reflections from the World of Diamonds

• The Mellon Blue Sold at Auction

Among the events that stood out on the global jewelry scene, special attention goes to the Christie’s auction held in Geneva on November 9, featuring the Mellon Blue. This exceptional 9.51 carat pear shaped diamond, distinguished by its vivid blue color and flawless clarity, was sold for 25.6 million dollars, a result that once again confirms the extraordinary appeal of truly exceptional colored diamonds.

The Mellon Blue came from the private collection of Rachel Lambert Mellon, better known as Bunny Mellon, a legendary American art patron, landscape designer, and iconic symbol of understated elegance. Bunny Mellon, who passed away in 2014 at the age of 103, is widely remembered for redesigning the White House Rose Garden with Jacqueline Kennedy in 1962 and for curating a jewelry collection with the same refined sensibility she applied to art and interiors.

Blue diamonds of this quality are extremely rare. They account for less than one tenth of one percent of all diamonds ever mined, and only a very small number achieve the Fancy Vivid Blue classification. With its perfectly balanced pear shape, rich color saturation, and immaculate transparency, the Mellon Blue stands as one of the most important modern era blue diamonds ever sold at auction.

• Saks Fifth Avenue and the Return of MagicNatural Diamonds at the Heart of New York

The holiday season opened in November under the sign of the natural beauty of gemstones. New York became the stage for a moment of strong symbolism for the diamond world. The government of Botswana and De Beers, the world’s leading diamond mining group, formed a remarkable partnership with Saks Fifth Avenue to present the famous Fifth Avenue Holiday Light Show, marking the return of the iconic display after a one year absence.

The decision to bring the show back represents a symbolic return to the grandeur of luxury consumption in New York. Saks transformed the façade of its Fifth Avenue flagship store into a luminous orchestra, adorned with sparkling references to natural diamonds and synchronized to a themed soundtrack ranging from Rihanna’s Diamonds to contemporary holiday compositions. The show, repeated every ten minutes, attracts thousands of visitors from around the world. The display features dozens of gem shaped light installations, some nearly two stories tall, with reflective surfaces and prismatic effects designed to evoke diamonds and precious stones.

This collaboration between Botswana, De Beers, and Saks is far from coincidental. It reflects a coordinated effort by the global diamond industry to reaffirm the value of natural diamonds at a time when comparison with lab grown stones has become increasingly prominent. Thanks to millions of viewers, both in person and online, the partnership achieved global visibility, positioning natural diamonds once again as symbols of a centuries old luxury tradition that still has the power to inspire and captivate.

Conclusion

The data from November 2025 show that diamond values are under significant structural pressure. In this environment, having a clear and accurate understanding of what one owns and its true value is the essential foundation for any informed decision, whether the goal is to preserve an investment, pass it on to future generations, or liquidate it when life circumstances require.

Auctentic offers a discreet, transparent, and personalized approach for those who wish to understand and enhance their assets with the same care reserved for what truly matters. Request a confidential valuation of your diamonds or jewelry and discover how their value can be transformed into new opportunities, guided by our expert gemologists.

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