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

During its Q3 call, CEO Efraim Grinberg discussed the deal to lower tariffs on Swiss-made watches, watch market trends, and more.

Rosior’s high jewelry cocktail ring with orange sapphires and green diamonds is the perfect Thanksgiving accessory.

The “Embrace Your True Colors” campaign features jewels with a vibrant color palette and poetry by Grammy-nominated artist Aja Monet.

How Jewelers of America’s 20 Under 40 are leading to ensure a brighter future for the jewelry industry.

Luxury veteran Alejandro Cuellar has stepped into the role at the Italian fine jewelry brand.


The company gave awards to four students at the Namibia University of Science & Technology, including one who is a Grandview Klein employee.

She is remembered as an artist who loved her craft and was devoted to her faith, her friends, and her family.

Roseco’s 704-page catalog showcases new lab-grown diamonds, findings, tools & more—available in print or interactive digital editions.

The polka dot pattern transcends time and has re-emerged as a trend in jewelry through round-shaped gemstones.

Vanessa Hickman, 49, allegedly sold a diamond bracelet that was mistakenly sent to her home.

GIA’s former president and CEO was presented with the Richard T. Liddicoat Award for Distinguished Achievement.

Social media experts spoke about protecting brand reputation through behaving mindfully online.

In 2026, the three will come together as “House of Brands,” with Gallet sold in Breitling stores and Universal Genève sold separately.

The second drop, which includes more Elphaba-inspired pieces from additional designers, will continue to benefit nonprofit Dreams of Hope.

Second-generation jeweler Sean Dunn has taken on the role.

Amber Pepper’s main focus will be on digital innovation and engaging younger consumers.

The lariat necklace features a 4.88-carat oval-cut Zambian emerald in 18-karat yellow gold.

A 43-carat sapphire brooch from the Vanderbilt collection was the top lot of the Geneva sale.

Rau is a fourth-generation art and antique dealer from M.S. Rau gallery whose first jewelry collection merges artifacts with modern design.

Former De Beers sustainability leader Purvi Shah will take over the role in February 2026.

La Joux-Perret is based in La Chaux-de-Fonds, Switzerland, and makes solar quartz as well as mechanical watch movements.

She previously taught at Gem-A and is the founder of The Gem Academy.

The British actress and her daughter modeled pieces from the brand’s new “Palette” capsule for its “Once Upon a Time” holiday campaign.

Plus, the tech giant shares the steps retailers should take if they believe they’re a victim of a review extortion scam.

Danny and Gaby Shaftel are now Shaftel Diamonds’ CEO and chief operating officer, respectively.

The jewelry manufacturer’s seasonal offering features its new “Melodie” bangles, as well as mini stud earrings and layering pieces.

With more than 140 activations taking place in New York City now through Nov. 23, these 12 events are can’t-miss moments.

























