Donald Bowers/Getty Images North America/Getty Images for Sotheby's
The 1,109-carat Lesedi La Rona first made headlines last June, when its seller, Canada's Lucara Diamond Corp, broke with tradition and offered the uncut stone at a Sotheby's auction (most rough diamond sales are completed privately), with an estimated price set at $70 million.
Graff
Graff chairman Laurence Graff with the 102.79-carat Constellation, the world's largest D-colour, internally flawless round diamond, which was cut from Graff's Light of Letšeng 478-carat rough.
Graff
The Graff Eternal Twins, two identical 50.23ct emerald-cut gems, were cut from a 269-carat rough diamond.
de Grisogono
De Grisogono founder and creative director Fawaz Gruosi with the 404-carat "4 de Fevereiro" diamond, the the largest rough diamond discovered in Angola.
de Grisogono
De Grisogono's emerald and diamond necklace took 1,700 hours to create and features the largest flawless D-colour diamond (163.41 carats) to ever to come to auction. It's expected to fetch around $30 million at Christie's Geneva on Nov. 14, 2017.
de Grisogono
Last year De Grisogono acquired the 813-carat Constellation, billed as the world's most expensive rough diamond.
Chopard
Chopard co-president and artistic director Caroline Scheufele says she still "gets goose bumps" seeing the suite of gems she created from a 342-carat rough that produced 23 diamonds.
Chopard
"I wanted to explore every possibility and to represent all diamond cuts," said Scheufele of the 342-carat D flawless rough.
Chopard
The highlight of Chopard's Garden of Kalahari necklace is a 50-carat brilliant-cut diamond.
Chopard
Carla Bruni (left) and Eva Herzigova (right), seen here with with Chopard co-president Caroline Scheufele, were among the guests at the Garden of Kalahari launch during Haute Couture Fashion Week in January.
De Beers
Rough diamonds are not only the preserve of the ultra-rich. In 2005 De Beers launched the Talisman collection featuring a mix of rough and polished diamonds. The collection included this medallion with 0.8-carats of stones (£3,650).
CNN  — 

High jewelry houses are traditionally at the tail end of the diamond supply chain. Once they’re extracted, rough stones are typically acquired by specialist diamond cutters and polishers, who analyze each stone – sometimes for up to a year – to determine the ideal cut in which to shape them. Only after this process are the polished gems usually presented to high jewelry houses, who set them into glittering creations.

But now a handful of houses are keen to master all stages of a stone’s journey from rough to final jewel. In September, for example, British luxury jewelers Graff Diamonds bought the uncut Lesedi La Rona, the world’s second largest diamond, for $53 million.

Graff
The Graff 'Eternal Twins' hail from a 269-carat rough, cut into two identical 50.23ct emerald-cut gems.

“It’s become en vogue for brands to say they’ve acquired a rough diamond, and organized the stone’s cutting and polishing,” says Vartkess Knadjian, CEO of the 228-year-old diamond company Backes & Strauss. “That provenance will have tremendous interest for the consumer.”

The 1,109-carat Lesedi La Rona first made headlines last June, when its seller, Canada’s Lucara Diamond Corp, broke with tradition and offered the uncut stone at a Sotheby’s auction (most rough diamond sales are completed privately), with an estimated price set at $70 million. When the stone failed to sell, the company sold it to Graff for almost $20 million less.

Company chairman Laurence Graff said he considers exceptionally large rough diamonds a “phenomenon and the most extraordinary discoveries on our planet.” The house has shaped at least 11 roughs in the past decade. In 2006, Graff presented the Lesotho Promise necklace with 26 D-color, flawless diamonds cut from a single 603-carat rough; and in 2016, Graff transformed four rough stones into five diamonds, including the identical, 50.23-carat, emerald-cut Eternal Twins.

“Our clients are excited to see what we will reveal from (rough stones),” Graff added.

Courtesy Sotheby's
A diamond ring purchased for ‎£10 ($13) sold for £656,750 ($847,667) at the Sotheby's Fine Jewels auction in London.
JUSTIN TALLIS/AFP/AFP/Getty Images
The ring sold for roughly double its initial estimated value of £250,000 ($325,000) to £350,000 ($456,000).
courtesy christies
The "Aurora Green" is the largest Fancy Vivid green diamond ever sold at auction. The stone went under the hammer on May 31, 2016 at Christie's auction house in Hong Kong, selling for $16,818,983.
Christies Images Ltd 2016
The world's largest blue diamond, an extremely rare gem known as "The Oppenheimer Blue", sold for $57.5 million at Christie's Geneva May 18, 2016. The 14.62 carat Fancy Vivid stone is mounted on a platinum ring and flanked on either side by a trapeze-shaped diamond.
courtesy sotheby's
'The Unique Pink' is the largest Fancy Vivid pink pear-shaped diamond to ever be offered at auction.
courtesy sotheby's
The diamond was sold for $31.6 million by Sotheby's, at an auction in Geneva. The price makes it the most expensive Fancy Vivid pink diamond to sell at auction.
Bloomberg/Bloomberg/Bloomberg via Getty Images
Cubic zirconia replicas of the original and a modern cut of the Kohinoor diamond, one of the oldest and most famous diamonds in the world.
Sotheby's
Sotheby's auctioned this 9.54 carat ring it says belonged to child star Shirley Temple on April 19, 2016. Though it was expected to fetch between $25 million and $35 million, it failed to sell.
FABRICE COFFRINI/Getty Images
This 12.03-carat blue diamond fetched $48.4 million at auction on November 11, 2015. It was previously the world's most expensive price-per-carat diamond sold.
FABRICE COFFRINI/Getty Images
The fancy, vivid blue diamond was discovered in South Africa in January last year.
Peter Macdiarmid/Getty Images Europe/Getty Images
This 118.28 oval white diamond became the largest sold at auction when it went for $30.6 million at a Sotheby's auction in 2013.
Courtesy Sotheby's
In April 2015, a 100-carat, emerald cut, D color, internally flawless diamond -- the largest of its clarity and cut to ever be shown at auction -- sold for $22 million.
FABRICE COFFRINI/AFP/Getty Images
The 76.02-carat 400-year-old Archduke Joseph diamond set a new record for price per carat for a colorless diamond in 2012, when it sold for $21.5 million at a Christie's auction.
Courtesy Chow Tai Fook
In 2010, Hong Kong's largest jewelry retailer, Chow Tai Fook, bought one of the world's largest rough diamonds for $35.3 million.
Courtesy Chow Tai Fook
Jeweler Wallace Chan and a team of craftsman worked 47,000 hours to transform the stone it into this piece, which Chai Tai Fook estimates could be worth $200 million.

As one of few high jewelry houses with its own cutting and polishing capabilities, Graff has an obvious advantage when it comes to processing rough diamonds in house. But a lack of such infrastructure hasn’t stopped other firms from trying: 25-year-old Swiss jeweler de Grisogono recently entered a ground-breaking partnership with Dubai diamond trader Nemesis International that essentially gives de Grisogono first dibs on whatever the company mines.

Fawaz Gruosi, founder and creative director of de Grisogono, was behind the company’s acquisition of the rights to the 404-carat “4 de Fevereiro,” the largest rough white diamond found in Angola, from Nemesis in May 2016. After it was discovered in the Lulo mine in Lunda Sul Province in February 2016, de Grisogono arranged for the stone to be analyzed in Antwerp, Belgium, before being sent to New York, where 10 diamond cutters mapped, plotted, cleaved, laser-cut and polished the gem over 11 months. The de Grisogono team then conceived and executed the final design in Geneva.

The result of this international effort, a 163.41-carat emerald-cut diamond suspended from an exquisite emerald-and-diamond necklace, is currently on a world tour, and will go under the hammer at Christie’s Geneva on Nov. 14. It’s expected to fetch around $30 million.

“Other surprises are in the pipeline,” said Gruosi of the brand’s rough diamond agenda. “This is just the beginning.”

Buying rough stones directly from reputable dealers and mines can also give jewelers greater peace of mind. When you know the source of your stones, you can seek out the appropriate assurances that they were mined and sold under fair conditions.

Chopard
Chopard co-president and artistic director Caroline Scheufele says she still "gets goose bumps" seeing the suite of gems she created from a 342-carat rough that produced 23 diamonds

This has been a draw for Caroline Scheufele, co-president and artistic director of Chopard, who launched a campaign to bring more eco-friendly practices to jewelry-making in 2013. This passion for sustainability led her to the discovery of a 342-carat, D-color, flawless rough from Botswana’s Karowe mine, one of the world’s first diamond mines to achieve a Fairmined certification, which denotes responsible mining practices. The rough was christened the Queen of Kalahari and produced 23 diamonds (five of which are over 20 carats), which were set into a suite of six outstanding jewels.

Chopard unveiled the resulting Garden of Kalahari collection at a celebrity-studded bash during Paris Haute Couture Week this past January, and it was later displayed in cities around the world, including Tokyo and Cannes.

“People increasingly want to know the whole supply chain,” Scheufele said. “No matter what industry – whether fashion, architecture or cars.”