26+ Ct. Diamond Expected to Sell for Over $1M in London Auction

By Annie Davidson Watson | March 16, 2026

The largest white diamond solitaire to be auctioned in the U.K. in nearly a decade is set to headline Elmwood’s Fine Jewellery sale tomorrow, and is expected to fetch over a million dollars.

Carrying an estimate of £800,000 to £1,000,000 (approximately $1.07 million to $1.34 million), the 26.36 ct. round brilliant-cut stone boasts VVS1 clarity and I color. To maximize visual impact, the diamond is mounted in a simple platinum ring.

Crucially for collectors, the diamond has achieved “triple excellent” status—the highest possible grades for cut, polish, and symmetry. An absence of fluorescence further ensures the diamond’s “brilliance and fire” remain crisp under any lighting.

elmwoods diamond ring

“This is an extraordinarily rare diamond,” said Joe Kendrick, head of sale at Elmwood’s, in a statement. “Its combination of size, VVS1 clarity, and triple excellent cut is something you simply do not see in the U.K. market. Stones of this calibre come along perhaps once in a decade, and this solitaire is a spectacular example of what makes white diamonds so prized by collectors worldwide.”

The last comparable stone in a U.K. auction was a 26.27 ct. white diamond sold by Sotheby’s in 2017 for £656,750. That diamond, called the Tenner, gained fame after it was revealed that the owner had purchased it for just £10 at a car boot sale (like a flea market).

Elmwood’s 26.36 carater represents a significant achievement for both the London auction house, which was founded in 2017, and for the British secondary market, since diamonds of this magnitude are seldom on the block outside Geneva or New York.

Based in Notting Hill, Elmwood’s has positioned itself as a disruptor by offering 0% seller fees, attracting high-value consignments that traditionally head to larger international houses.

(Photos courtesy of Elmwood’s)

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