Petra Puts 39-Carat Blue Diamond Up for Sale
The stone, which is similar to the rough diamond that produced the “Blue Moon of Josephine,” is expected to sell for upward of $50 million.

Viewings of the 39.34-carat, Type IIb stone will take place throughout June and into early July, including a stop in New York from July 7-9.
Tender bids are scheduled to close on or around Monday, July 12 at 10 a.m. EDT.
In an interview with National Jeweler last week, George Togholian, a gemologist at L.J. West Diamonds, compared the 39.34-carat diamond to another big chunk of blue rough mined at Cullinan in January 2014—the 29-carat stone that became the $48.5 million “Blue Moon of Josephine.”
New York-based Cora International cut that stone, and Togholian, who worked as a gemologist and consultant for the company then, helped with the planning process.
Though he has not seen the 39.34-carat rough diamond in person yet, he said in pictures it looks “very similar” to the rough that produced the Blue Moon, possessing the color and texture specific to blues from Cullinan.
“This is a special tone of blue. It’s not comparable to any other diamond that comes to auction,” Togholian said.
“In my opinion, these are the best of the blues. This is on another level.”
While he declined to share his guess as to the diamond’s sale price, Togholian did note the 39-carat rough probably will deliver about a 40 percent yield—the yield for blues and pinks is generally less than yellow or white diamonds because the material is not as smooth, he noted—which means a polished diamond of about 15 to 16 carats.
That’s 3 to 4 carats larger than the 12.03-carat Blue Moon of Josephine, which still holds the world auction record for highest-grossing gemstone per carat at $4 million.
Joseph Namdar, of Namdar Inc., described the 39.34-carat blue rough as a “very special diamond” that is “thought to be one of the purest blues to ever be mined.”
While noting bidding is unpredictable, he put the rough diamond’s sale price at $55 million to $65 million.
The Cullinan mine has produced a number of famous diamonds, including, of course, the 3,106-carat Cullinan, the rough that produced the 69-carat Taylor-Burton Diamond, and the aforementioned 29-carat blue rough that became the Blue Moon of Josephine.
Anyone interested in scheduling a viewing of the 39.34-carat blue diamond should contact Petra’s Group Head of Sales and Marketing Greg Stephenson at diamondsales@petradiamonds.com or +27 836 379 849.
The Latest

The company plans to raise the prices of select watches to offset the impact of tariffs.

Between tariffs and the sky-high cost of gold, designers enter this year’s Las Vegas shows with a lot of questions and few answers.

Designed by founder Renato and his daughter Serena Cipullo, it showcases a flame motif representing unity and the power of gathering.

More shoppers are walking out without buying. Here’s how smart jewelers can bring them back—and the tool they need to do it right.

However, the tariffs remain in effect in the short term, as an appeals court has stayed the U.S. Court of International Trade’s decision.


The pop icon is one step closer to launching her “B Tiny” jewelry collection, a collection she first began posting about last fall.

Sponsored by Stuller

Gain access to the most exclusive and coveted antique pieces from trusted dealers during Las Vegas Jewelry Week.

GemText AI uses artificial intelligence to generate tailored product titles, descriptions, and tags with jewelry-specific language.

The 3,300-square foot location is the jeweler's largest store in North America.

Aging and with myriad health issues, none will serve time for their roles in robbing the billionaire celebrity at gunpoint in 2016.

The WNBA team received rings imbued with meaning, from leaf motifs and its Liberty torch to the number of diamonds used.

A longtime executive at RDI Diamonds, Rickard has served on the JBT board for the past five years.

The two organizations have signed an affiliation agreement that’s expected to be finalized in the coming weeks.

The platinum and diamond watch is part of Sotheby’s upcoming Important Watches sale.

Recovered in Mozambique, “The Kat Florence Lumina” was part of Bonhams’ Hong Kong jewelry auction held last week.

Get a taste of the delicious candy-like gemstones in this Amanda’s Style File.

JSA’s Scott Guginsky provided a list of nine security measures jewelers should observe while locking up for the long weekend.

From Lau’s “Love of a Kind” series, the engagement ring was inspired by the moon and holds a different meaning depending on how it is worn.

The lab has adjusted the scale it uses for nacre grading.

Sponsored by GCAL by Sarine

David Walton will serve three years’ probation after an incident in a hotel bar led to the death of West Virginia jeweler David Ettinger.

The retailer also provided an update on how the tariffs situation in the U.S. is affecting its business.

The family-owned jeweler in Great Falls, Virginia, will be celebrating its golden jubilee with a year’s worth of events.

The nonprofit elected five judges who will decide the winners of its design competition.

This year’s edition includes articles on the favorite tools of notable designers, evaluating when to outsource production, and more.

The jeweler’s high jewelry collection features extraordinary gemstones, like a 241.06-carat emerald and the world’s fourth-largest spinel.