AuctionsOct 24, 2025
Bonhams Under New Ownership, Top Executives ReplacedLondon-based investment firm Pemberton Asset Management acquired the auction house for an undisclosed amount.
SourcingFeb 24, 2021
157-Carat Canadian Diamond Goes Up for Sale
Dubbed “Polaris,” the rough diamond is the Gahcho Kué mine in Canada’s Northwest Territories’ largest gem-quality diamond recovered to date.
Mountain Province Diamonds and De Beers Group recovered this nearly 160-carat diamond from the Gahcho Kué mine in Canada. It’s the largest gem-quality diamond the mine’s yielded to date. (Photo courtesy of Mountain Province Diamonds)
Toronto—The big gem-quality diamond recovered from Canada’s Gahcho Kué mine in December is up for sale.
The diamond is 157.38 carats and is described as a gem of “exceptional quality” that exhibits natural blue fluorescence.
This fluorescence appears in the stone at an “intriguing level,” said Reid Mackie, vice president of diamond marketing at Mountain Province Diamonds, which operates Gahcho Kué in partnership with De Beers Canada.
He called the phenomenon a “natural hallmark” of the diamond’s northern origins, and compared it to another natural phenomenon that occurs in the area where the mine is located, the aurora borealis, or northern lights.
Mackie also noted that blue fluorescence—a trait long shunned by the diamond industry—is now “a quality for which some of our leading customers have created unique marketing platforms.”
Mountain Province named the nearly 160-carat stone “Polaris,” after the North Star.
Mackie declined to provide a pre-sale estimate, noting the lack of comparisons available due to the diamond’s size. The stone is the largest rough diamond the mine has yielded in its approximately four-year history.
Mackie declined to provide a pre-sale estimate, noting the lack of comparisons available due to the diamond’s size. The stone is the largest rough diamond the mine has yielded in its approximately four-year history.
“We really haven’t yet seen an equivalent against which to compare it to, which makes the sale all the more exciting for us and our customer base,” he said.
RELATED CONTENT: Take a Peek at the Largest Diamond Found in North America
The Polaris is part of Mountain Province’s February sale being conducted now at Bonas Group’s offices in Antwerp.
In addition to Polaris, the sale includes more than 30 high-quality diamonds weighing 10.8 carats or more, the company said, as well as Mountain Province’s customary run-of-mine assortments.
Viewings started Monday and run through early March. The sale is scheduled to close on March 5 at 3 p.m. CET via online highest-bid tender.
Mountain Province Diamonds operates Gahcho Kué in 49/51 percent joint venture with De Beers Canada.
The mine started production in September 2016 and, the company said, has established itself as a source of larger, high-quality diamonds.
On Feb. 8, Mountain Province announced it was temporarily shutting down Gahcho Kué due to an outbreak of COVID-19. The company said Tuesday it is “hopeful” normal operations will resume in the near future. Parties interested in bidding on the Polaris, or any diamond in Mountain Province’s February sale, should call Bonas-Couzyn NV at +32 (0)3 233.
More on Sourcing
The Latest
GradingOct 24, 2025
DMIA to Hold Diamond Testing Instrument DemoThe workshop will give attendees the chance to try out and ask questions about three different diamond verification instruments.
CrimeOct 24, 2025
Video Emerges of Louvre Jewelry Robbers Fleeing the Scene The footage shows two of the jewelry heist suspects descending from the second floor of the museum and then escaping via scooter.
Brought to you by
Are Earrings an Overlooked Category? What Retailers Need to Know NowAs the holiday season quickly approaches, consider stocking one category that sometimes gets overlooked: earrings.
CollectionsOct 24, 2025
Piece of the Week: Wyld Box Jewelry’s ‘Ray of Light’ EarringsFounder and designer Rosanna Fiedler looked to a vintage Cartier clutch when designing the sunlight-inspired drop earrings.
Weekly QuizOct 16, 2025
This Week’s QuizTest your jewelry news knowledge by answering these questions.
FinancialsOct 23, 2025
Jewelry Sales Resilient Despite Struggles at LVMH, KeringThe luxury conglomerates faced a challenging Q3 amid geopolitical and economic tensions.
WatchesOct 23, 2025
‘Million Dollar Hip Hop Watches’ Recounts Watch HistoryThe book details the journey of watches as symbols of hard-earned success in hip-hop for artists like 2Pac, Jay-Z, and more.
Brought to you by
Protect Your Customers and Your BusinessYou deserve to know what you are selling–to protect your customers as well as your business and your reputation.
AuctionsOct 23, 2025
Freeman’s | Hindman Names New VP, Senior Specialist for Jewelry & WatchesAlexis Vourvoulis, who most recently worked at Tiffany & Co., brings more than two decades of jewelry experience to her new role.
TrendsOct 22, 2025
The Taylor Swift Effect: Antique Diamonds EditionThe superstar’s August engagement put the stamp of approval on an already hot engagement ring trend.
TrendsOct 22, 2025
Don’t Forget These Diamond Jewelry Trends When Stocking for the HolidaysRetailers should offer classic styles with a twist that are a perfect fit for layered looks, experts say.
AuctionsOct 22, 2025
Pink Diamond, Vanderbilt Jewels to Headline Phillips’ Geneva AuctionThe nearly 7-carat fancy vivid purplish pink diamond could sell for around $9 million.
CollectionsOct 22, 2025
Tiffany & Co.’s ‘Bird on a Rock’ Finds New PerchChief Artistic Officer Nathalie Verdeille has reimagined the iconic design in both figurative and abstract creations.
Events & AwardsOct 22, 2025
JFC Kicks Off Halloween Costume ChallengeFive dollars buys one vote toward an industry professional you want to see dressed up as a hero, or a villain, this Halloween.
Events & AwardsOct 22, 2025
Hillsborough Antique Show Gets New OwnerRecently acquired by KIL Promotions, the November edition of the public show in San Mateo, California, will be held Nov. 7-9.
GradingOct 21, 2025
GIA Examines Rare Bicolor Pink DiamondThe stone’s two zones, one pink and one colorless, may have formed at two different times, the lab said.
MajorsOct 21, 2025
Pomellato Brings ‘Global Attitude’ to Rodeo Drive FlagshipHollywood glamour meets Milanese sophistication in the design of Pomellato’s new store in Beverly Hills, California.
Lab-GrownOct 21, 2025
Grown Brilliance Opens First FlagshipThe New York City store showcases a chandelier with 1,500 carats of lab-grown diamonds designed by an FIT student.
Events & AwardsOct 21, 2025
‘Douriean Fletcher: Jewelry of the Afrofuture’ Opens at MADThe Museum of Arts and Design's new exhibition features 75 pieces by the designer, best known for her work in the “Black Panther” films.
AuctionsOct 20, 2025
Sotheby's To Auction 10-Carat Vivid Pink DiamondMaking its auction debut, "The Glowing Rose" is expected to fetch $20 million at the November jewelry sale in Geneva.
SourcingOct 20, 2025
2 Mozambique Police Officers Killed at Gemfields’ Ruby MineThey were attacked on Oct. 15, as approximately 40 miners without licenses marched on the mine’s gate.
CrimeOct 20, 2025
See the ‘Priceless’ Jewels Stolen During Daytime Heist at the Louvre It took the masked thieves less than 10 minutes to steal eight irreplaceable jewels from two display cases in the museum’s Apollo Gallery.
SourcingOct 20, 2025
Pristine Gems Names New Director of European SalesGemologist Lauren Gayda has previously worked at The Clear Cut, Taylor & Hart, and Effy Jewelry.
IndependentsOct 17, 2025
From the Jazz Age to the Information Age: London Jewelers Turns 100In 2026, the jewelry retailer will celebrate a milestone only a small percentage of family-owned businesses survive to see.
Events & AwardsOct 17, 2025
An Edit of Italian Jewels Is Coming to NYCThe new showcase dedicated to Italian jewelry design is set for Oct. 29-30.
TrendsOct 17, 2025
Piece of the Week: Judi Powers Jewelry’s ‘Stella’ EarringsTake a gaze at the sky with this pair of platinum diamond-set star earrings with blue lace agate drops.
IndependentsOct 16, 2025
Retailer Hall of Fame 2025: Jeffrey Zimmer Jeffrey Zimmer's decades of leadership at Reeds Jewelers are defined by integrity, a love of sourcing gemstones, and a heart for community.
