Relatively small, but slowly and perfectly formed over billions of years, the Argyle Violet diamond is so rare in color that it has its own unique diamond classification: “Fancy Deep Grayish ...

Rio Tinto (LON:RIO) unveiled Tuesday a rare 2.83-carat violet diamond, the largest of its kind ever found at Australia’s remote Argyle mine, which could sell for more than $4 million.

(Mr. West should know. In 2016, he purchased a 2.83-carat oval-shaped violet diamond at Rio Tinto’s annual silent tender, a trade auction of its small but extremely valuable cache of rare pink ...

Rio Tinto said violet diamonds were extremely rare with only 12 carats of polished stone produced for the tender in 32 years. Sydney, Australia: A rare violet diamond, the largest of its kind ever ...

“At 2.83 carats, this is the largest and most valuable violet diamond ever recovered from the Argyle mine,” says Mr West, founder of New York’s LJ West Diamonds. “You could fill a garbage ...

The showpiece is the Argyle Violet, a violet diamond surrounded by pink diamonds and set in a platinum ring. Owner and exhibition partner, diamond collector L.J. West Diamonds, believes it is the ...