The 3.14-Carat ‘Alpha’ Diamond in Rio Tinto’s Tender

Sydney—Rio Tinto just debuted the diamonds in this year’s Argyle Pink Diamonds Tender, its annual sale of the best pink, red and violet stones to emerge from its mine in Western Australia.

The 2018 tender comprises 63 diamonds totaling 51.48 carats. It’s bigger than last year’s offering, which had 58 diamonds totaling 49.39 carats and included the largest red diamond in tender history.

This year’s superlatives include the biggest vivid pink diamond in tender history, the 3.14-carat stone dubbed the “Argyle Alpha,” and the weightiest purplish-red, the 2.28-carat “Argyle Muse.”

The diamond mining company described the Muse as having “an unrivaled potency of color,” and noted that the 7.39-carat rough diamond from which it was cut yielded another stone in the 2018 tender, a 0.63-carat purplish-red stone.

The Muse and the Alpha are two of the diamonds selected as “hero stones,” the handful of diamonds Rio Tinto considers to be exceptional and names in each tender.

This year, there are a half-dozen heroes. Here is the complete list:
—Argyle Muse, a 2.28-carat fancy purplish-red oval;
—Argyle Alpha, a 3.14-carat emerald-cut fancy vivid purplish-pink;
—Argyle Maestro, a 1.29-carat square-cut fancy vivid purplish-pink;
—Argyle Alchemy, a 1.57-carat fancy dark gray-violet princess;
—Argyle Odyssey, a 2.08-carat fancy intense pink round brilliant; and
—Argyle Mira, a 1.12-carat fancy red radiant.

Each diamond, along with its name and characteristics, is pictured in the slideshow below.

The diamond mining company, which is based in Perth, Australia, and mines its colored diamonds at the Argyle mine in Western Australia, premiered the collection in Sydney Thursday.

The stones will travel next to Hong Kong in September (coinciding with the jewelry trade show there) and New York in early October, with bids closing Oct. 10.