Rising inventory is putting fresh pressure on polished diamond prices following a strong mid-year recovery. The Rapaport Spec Diamond Index (RAPI™) dropped across major smaller sizes in October—led by a 5.5% plunge in 0.30-carat stones and a 2.3% slide in 0.50-carat goods after late-September peaks.

Mid-sized 1-carat diamonds edged down 0.9%, while larger 3-carat stones bucked the trend with a modest 0.9% gain. Despite the retreat, 0.30-carat diamonds remain up 8.8% year-to-date.

​Inventory Floods Small Sizes: Supply of 0.30-carat rounds surged 165% between June 1 and November 1, driven by ramped-up factory production and cutters sending smaller stones back for grading as prices recovered.

Rough Sales Slow Ahead of Diwali: Indian manufacturers are shuttering factories for up to a month for Diwali, dampening rough demand and dragging down De Beers’ October sight sales. Industry observers expect the holiday pause to help balance bloated inventories.

​Luxury Brands Outshine the Trade: While upstream pricing softens, major luxury conglomerates continue to thrive. LVMH and Kering posted robust Q3 jewelry revenue, setting high expectations heading into the critical holiday shopping window.