De Beers Group and Sotheby’s have unveiled a rare 28.88-carat internally flawless diamond from Botswana’s Jwaneng mine, marking its first public appearance ahead of an upcoming auction.
The stone, known as the Jwaneng 28.88, was presented at Maison Assouline in London during a special showcase attended by industry guests. Described as a “masterpiece of nature and craftsmanship”, the diamond highlights the exceptional quality associated with the Jwaneng mine, one of the world’s richest diamond sources.
The diamond is a D-colour stone — the highest colour grading — and falls within the rare Type IIa category, representing the purest form of natural diamonds. It was cut from a 114.83-carat rough recovered from the Debswana-operated Jwaneng mine in Botswana.
The unveiling forms part of a broader collaboration between De Beers and Sotheby’s, with the stone set to headline Sotheby’s High Jewellery sale in Hong Kong on 23rd April 2026. The diamond is expected to attract significant interest from collectors, given its size, clarity and provenance.
The London event also coincided with a cultural showcase celebrating the legacy of diamonds, featuring curated works and archival material that explore the relationship between diamonds, art and design.