First Diamonds from Sierra Leone’s Tongo Mine Coming to Market
Australian company Newfield Resources is developing the mine and will sell its production through Bonas Group in Antwerp.

Newfield Resources Ltd., the company developing the mine, announced in late April it had inked an exclusive diamond sales and marketing agreement with Bonas for the mine’s production.
Via its partnership with Bonas, Tongo goods will be tracked from mine to market using Sarine Technologies’ traceability program, Newfield said.
The mine, which has been in the works for more than decade, is “well known for its high-quality material,” Bonas said.
Tender viewings of the Tongo material will take place on the first floor of the Bonas Group offices in Antwerp between May 16 and 20.
The sale is scheduled to close May 20 at 1 p.m. CET/7 a.m. EDT and will be an online, highest bid tender on Newfieldbids.com.
Bookings for the tender are invitation-only, but requests can be submitted to Bonas Antwerp. Interested clients are requested to call the office at +32 (0) 3233 7080.
Based in Australia, Newfield has been developing the Tongo Diamond Project since 2018, when it acquired the site from Stellar Diamonds.
The project comprises two adjacent mining licenses covering a combined area of 134 square kilometers (about 52 square miles) in eastern Sierra Leone with five primary kimberlite pipes.
The first two pipes Newfield will mine have been dubbed Kundu and Lando.
Newfield said processing from the underground and surface at Kundu continues to yield “encouraging results,” with a high proportion of what’s recovered turning out to be gem-quality diamonds.
It is believed Tongo will produce 8.3 million carats of diamonds over the span of its life, including an indicated and inferred resource of 3.03 million carats at Lando and 2.76 million carats at Kundu.
Newfield employed 200 people at the mine as of March 31, including graduate trainees, contractors, and interns. Of the 200, 166 (83 percent) are local Sierra Leonians and 128 (64 percent) have permanent employment contracts, it said.
Twelve percent (about 20 people) of the local employees are women. Newfield said it intends to increase the number of women working at the mine, in line with its diversity policy.
In addition to Tongo in Sierra Leone, Newfield is conducting diamond exploration in neighboring Liberia via two licenses covering 670 square kilometers (about 259 square miles), known collectively as the Kumgbo Kimberlite Project.
The Latest

Smith shares wisdom he gleaned from a podcast he was listening to one morning while being walked by his dog, a Malshi named Sophie.

The counterfeit Van Cleef & Arpels jewels would have been worth more than $30 million if genuine.

The MJSA Mentor & Apprenticeship Program received the Registered Apprenticeship Program designation by the U.S. Department of Labor.

Jewelers of America is leading the charge to protect the industry amidst rising economic threats.

Casio executive and watch enthusiast Masaki Obu is the new general manager of its U.S. timepiece division.


Barabash, Verragio’s client relations representative, was a vital member of the team and is remembered as being warm and full of life.

Originally introduced in 1992, the “Dot” collection is back with a capsule featuring five archival designs and three new creations.

As a leading global jewelry supplier, Rio Grande is rapidly expanding and developing new solutions to meet the needs of jewelers worldwide.

Allison-Kaufman has received the honor for the fourth year in a row.

The company had a solid second quarter, with sales of non-charm jewelry outpacing sales of pieces in its core collections.

Taylor Swift dons the vibrant pair in new promotional imagery for her upcoming album, “The Life of a Showgirl,” set to release in October.

Its investment in micromechanics expert Inhotec will preserve skills essential to the watchmaking industry as a whole, said the company.

Nicolette Bianchi joins the wholesale provider with more than 15 years of cross-industry experience in marketing and product development.

Her new “Ocean” collection was inspired by Myanmar’s traditional articulated fish jewelry, with depictions of flounder, catfish, and more.

Longtime Casio executive Yusuke Suzuki is the new president and CEO of Casio’s U.S. subsidiary.

Model Georgina Rodríguez received a rock of an engagement ring, with her diamond estimated to be 35 carats, experts say.

The board elected 9 new directors at its recent ICA Congress in Brazil.

Three winners will receive a custom ring from Honest Hands Ring Co. inlaid with a piece of history from Denver-based distillery Stranahan’s.

JD Sports and Wawa were among the fastest-growing retail companies in the U.S. last year.

The new inventory, all untreated, features vibrant hues and unique bicolor combinations.

Acquired by a tech investor, the historic brand will continue to focus on jewelry, accessories, and timepieces.

President Donald Trump issued an executive order extending the pause on higher tariffs to November as negotiations with China continue.

The “Thunderbird Slab” collection features a thunderbird motif as a symbol of power, protection, and boundless possibility.

Columnists Jen Cullen Williams and Duvall O’Steen share tips on how to elevate your professional image.

Peter Damian Arguello, a jeweler in the Denver suburb of Wheat Ridge, was found dead inside his store in November 2023.

The retailer, owned by Berkshire Hathaway, is becoming part of the Berkshire Hathaway Jewelry Group with Helzberg.

The Continental Buying Group’s 2025 Tampa Experience Show is slated for Sept. 8-10.