A 52.5 carat diamond ring from the Golconda mine in Calcutta, India made $10.9m at Christie's New York on December 10.
Famed for the production of superior stones, products of the Golconda mine are highly prized. The ring features a large rectangular-cut diamond accompanied by two smaller diamonds either side.
Other items in the sale included a 26.7 carat ring by Leviev which sold for $4.3m, and a diamond pendant by the same brand which realised $.7m.
Sign up to our free newsletter for the latest on jewellery and other collectibles.