Steady Gains Ahead of the Holidays: September’s Market and Industry Highlights

Diamond prices extended their recovery into September. Rapaport’s RAPI index for 1-carat stones rose 0.5% in August, the category’s first gain in 15 months, and 0.30-carat and 0.50-carat dossier stones advanced 2.0% and 2.5% respectively, while the 3-carat segment slipped 0.4%. Prices held steady through mid-September, with elongated cushion shapes commanding a 20% to 25% premium over square cuts and Hong Kong’s show drawing steady but cautious demand for 2-carat-plus stones. Mining revenue declined over the same period: Alrosa’s first-half 2026 revenue fell 36% year over year to $901.6 million, and De Beers’ revenue dropped 19% to $1.58 billion. Retail indicators pointed toward a strong holiday season. Macy’s raised its full-year sales guidance to between $21.68 billion and $21.83 billion after second-quarter profit nearly doubled to $169 million on strength in fine jewelry, and Mastercard projected US holiday sales will rise 6% year over year, the strongest growth in four years. Auction houses posted solid results: Sotheby’s Hong Kong sale totaled $34.1 million across more than 180 lots, led by a pair of Cartier Tutti Frutti earrings that sold for nearly ten times their high estimate, and Heritage Auctions’ Dallas sale brought in $7.6 million, topped by a 22.09-carat fancy-yellow diamond ring at $475,000.

Organizational news centered on leadership and industry standards. The American Gem Trade Association elected four new board directors, Dudley Blauwet, Sailesh Lakhi, Cynthia Renee Marcusson and Ron Rahmanan, with Rohan Agrawal departed after six years of service. World Federation of Diamond Bourses president Mehul Shah called on governments to mandate local-language terminology for lab-grown diamonds and proposed a trademarked “Natural Diamond Mark” to distinguish mined stones. Rapaport’s own content turned toward the holiday season. The September issue of Rapaport Magazine covered holiday marketing strategy, gemstone and fashion trends, and retail cybersecurity preparation, and the fourth episode of Rapaport’s “Heard on the Street” video series, sponsored by BriteCo and presented with Shop LC, examined reputation, trust and scam stories within the trade.

Here’s your diamond market analysis from Rapaport Trade for October 2026

The 1ct RAPI rose 0.46% in September. Prices for 1.00 to 1.49 carat diamonds in D-J color moved up slightly. The average change across D-F and G-J in IF-VVS and VS was a positive 0.3%, a slightly slower pace than the 0.7% gain in August. The standout was K-M VS, which rose 3.9% after falling 0.3% in August. That was the largest swing in the table, a 4.2 point gain. K-M IF-VVS slipped 0.2%, versus a 2.1% gain the month before, so the K-M average for IF-VVS and VS reached 1.9%, up from 0.9%. SI clarity softened across all three color groups. D-F SI fell 0.9%, versus 0.0% in August. G-J SI fell 0.6%, versus a 0.6% gain. K-M SI fell 0.2%, versus a 0.6% gain.

The inventory mix remained stable, with only minor changes. D-F listings made up 31.2% of the category on October 1, up from 31.0% on September 1. G-J listings made up 62.1%, down from 62.7%. K-M listings made up 6.7%, up from 6.3%. The biggest move came in G-J SI, whose share fell to 16.7% from 17.5%, in line with the softer SI prices. G-J VS remains the largest single segment at 24.3%, unchanged from September 1.

Search demand stayed concentrated in two segments. G-J VS led with 22.5% of searches in August, up from 22.1% in July. D-F IF-VVS ranked second at 19.5%, down from 20.2%. The gap between the top two widened to 3.0 points, versus 1.9 points the month before.

Please note: the searches breakdown are a breakdown of buyers searches on Rapaport Trade

<<Click here>> to join the industry’s largest and most trusted 
diamond, gem and jewelry trading network.