Rio Tinto Holds Final Rare-Diamond Tender

November 12, 2025

Suzanne Watkin

Rio Tinto hosted its last Beyond Rare Tender, featuring 52 lots of polished fancy-colored diamonds, as the miner prepared to close its only remaining diamond deposit.

Titled “Into the Light”, the final collection showcased 45.44 carats of diamonds from the Argyle and Diavik mines. These included six “Masterpiece” sets, 39 single stones and an additional seven groups of diamonds, the miner said Tuesday. The Argyle pink, red, and violet diamonds came from the final legacy inventory, representing some of the last gems of their kind in the world.

“Presenting this final collection of Rio Tinto’s rarest diamonds is a wonderful epilogue to Rio Tinto’s inspiring story of mining and marketing diamonds,” said Patrick Coppens, general manager of sales and marketing for Rio Tinto’s diamond business.

One of the highlights was a lot comprising two pear-shaped. 0.25-carat, fancy-vivid-purplish-pink diamonds as well as an emerald cut, 5.11-carat, D-flawless from Diavik. The winner of this was Singapore-based Glajz in collaboration with Scandinavian luxury jeweler Hartmann’s.

Meanwhile, Japanese diamond company Kashikey won three lots, including a fancy-red diamond.

The tender attracted strong international participation, with individual, multiple, and collective bids from jewelers and collectors. The successful buyers originated from Europe, the US, Japan, Singapore, Hong Kong, Australia, and the Middle East, highlighting the sustained global demand for exceptional diamonds across leading consumer markets, the company said.

The mine held its third and last tender as the Argyle mine, which closed in November 2020, undergoes a planned rehabilitation process as part of its closure commitments. The Diavik site is scheduled to close in 2026, after which the company will no longer operate any diamond mines.

Image: Diamonds from the Beyond Rare tender. (Rio Tinto)