Gemfields has recovered a huge 11,685-carat (2.3kg) emerald – the biggest from its Kagem mine, Zambia, and possibly the biggest in the world.
The gemstone, called Imboo (the ‘buffalo’ in the local Bemba and Lamba dialects), eclipses the 7,525-carat Chipembele (the ‘rhino’), which was recovered at Kagem in July 2021, and which was recognized by Guinness World Records in April 2022 as the largest uncut emerald crystal recovered from a mine.
In January 2025, Almighty Gems in Coimbatore, India, displayed what it described as a record-breaking single emerald stone weighing 53,750 carats. But it has yet to be officially verified by an independent authority.
The newly-recovered Imboo emerald is being offered for sale at the Gemfields auction in Bangkok which runs until 11 September.
Jackson Mtonga, grading manager at the Kagem sort house, said: “In my 30 years at Kagem, I’ve rarely seen such a remarkable formation of large, high-quality crystals. This is a true masterpiece carved by nature’s hand.”
Imboo was discovered at Kagem’s Chama pit on 3 August by geologist Dharanidhar Seth, and Justin Banda, a veteran chiseller.
Australia-based jewelry retailer Michael Hill International says revenue for FY 2025 – the year to 29 June 2025 – was broadly flat compared with the previous year, down 0.2 per cent to AUD 643.7m (USD 431.3m).
Trading conditions remained challenging, it said, with the addition of volatile gold and diamond prices and US tariffs.
However group sales for the first seven weeks of FY 2026 were up 3.0 per cent year-on-year, and same store sales were up 3.2 per cent.
The company has 287 stores (down from 300 last year) in Australia, New Zealand and Canada, including low-price retailer Bevilles, Medley, and its new luxury business TenSevenSeven.
“Global economic uncertainty and challenging retail trading conditions persisted across all markets, with full year sales, gross margin and earnings broadly in line with prior year,” the company said in its Full Year Results, published yesterday (25 August).
Michael Hill chair Rob Fyfe paid tribute to CEO Daniel Bracken, aged 57, who died suddenly in February, and to founder Sir Michael Hill who died of cancer, aged 86, in July.
Taylor Swift and Travis Kelce’s engagement has captured global attention but it’s the diamond on Swift’s finger that has the jewellery world talking. The ring, created by Kindred Lubeck of Artifex Fine Jewelry, showcases what appears to be an old mine cut diamond, set in a delicate yellow gold bezel band. Its vintage charm, impressive size, and famous wearer have already made it one of the most talked-about engagement rings of the year.
What Makes Old Mine Cut Diamonds Special?
Old mine cuts are antique diamonds, hand-cut in the 18th and 19th centuries, before modern technology standardised proportions. Each one is truly unique, known for:
Chunky facets that give off a soft, romantic sparkle.
A high crown and small table, creating depth and character.
An open culet, a tiny facet at the bottom that adds to its antique charm.
Unlike today’s round brilliants, no two old mine cuts are ever the same—making them a perfect choice for those who want something one-of-a-kind.
The Value of Swift’s Diamond
Experts estimate Taylor’s diamond to be between 8 and 15 carats, with valuations ranging anywhere from USD $400,000 to over $1 million depending on its exact specifications. While few engagement ring budgets stretch quite that far, her choice highlights a rising trend: a return to antique and vintage stones.
Why Are Couples Choosing Antique Cuts?
In recent years, there’s been a growing interest in diamonds with personality and heritage. With the rise of lab-grown diamonds offering affordability and size, many buyers are instead turning to antique stones for uniqueness and history. As one jeweller put it: “Antique stones offer character you simply can’t replicate.”
A Timeless Trend
Taylor Swift’s engagement ring has brought the old mine cut back into the spotlight, and for many couples, it’s a reminder that engagement rings don’t have to follow the latest modern style. Choosing an antique cut is about more than sparkle—it’s about individuality, history, and wearing a diamond with a story.
At the Diamond Certification Laboratory of Australia (DCLA), we see growing demand for antique diamonds, and we understand why. They’re rare, distinctive, and timeless—just like the love stories they represent.
The volatility in the global diamond industry is beginning to have severe humanitarian and economic consequences across producer and manufacturing nations. Recent developments highlight the fragility of economies that rely heavily on diamonds, and the urgent need for market stability.
Botswana: Diamond Slump Triggers Public Health Emergency
Botswana, the world’s leading diamond producer by value, has declared a public health emergency after revenues from diamond sales halved in 2024. Production is expected to fall by at least 25 per cent this year, leaving the government with severe financial shortfalls.
Earlier today (25 August), President Duma Boko announced the emergency, citing a critical shortage of essential medicines. To address the crisis, 5 billion pula (USD 348m) has been reallocated from other government funds, while the state-owned Botswana Development Corporation has pledged 100 million pula (USD 7.3m). The president has also appealed to pension and insurance funds for support.
The military has been mobilised to distribute urgently needed medical supplies to rural areas. The Ministry of Health has identified shortages in medicines for hypertension, cancers, diabetes, asthma, eye conditions, tuberculosis, sexual and reproductive health, and mental health.
Although President Boko has referred to “market challenges” in official statements, local and international media have directly linked the crisis to collapsing diamond revenues, underlining the nation’s heavy dependence on the industry.
India: Tariffs Threaten 150,000 Diamond Jobs
In India, which processes the vast majority of the world’s diamonds, the industry faces a fresh crisis as the United States prepares to double tariffs on polished stones from 25 per cent to 50 per cent on 27 August.
The Diamond Workers Union Gujarat (DWUG), which represents a large section of Surat’s workforce, has warned Prime Minister Narendra Modi that the tariff hike could wipe out 150,000 to 200,000 jobs – nearly a fifth of India’s diamond workforce.
DWUG is urging the government to revive the Ratnadeep Scheme, originally introduced in 2008–09 during the global financial crisis. The scheme provided retraining opportunities and a daily stipend for unemployed diamond workers.
The union has also raised alarm over rising distress among workers, noting that at least 80 unemployed diamantaires have taken their lives in the last two years.
Zimbabwe: Building Closer Trade Links with India
While Botswana and India face mounting pressures, Zimbabwe is positioning itself to deepen diamond trade relations with India.
Vice President Constantino Chiwenga recently visited Surat to explore direct trade agreements that would bypass intermediaries. He also invited Indian investors to consider joint ventures in Zimbabwe’s mineral processing and industrial sectors.
With US tariffs on Zimbabwean diamonds set at 15 per cent – compared to India’s new 50 per cent rate – Zimbabwe sees an opportunity to attract Indian buyers and investors.
During the visit, Chiwenga met with leaders of Hari Krishna Exports to discuss partnerships aimed at moving Zimbabwe further up the value chain, from rough exports to local cutting, polishing, and manufacturing. Such developments could create significant employment opportunities, build local expertise, and reduce poverty in diamond-producing communities.
The Bigger Picture
These three stories highlight the immense global impact of diamond market fluctuations. For producer nations like Botswana and Zimbabwe, as well as manufacturing hubs like India, the stakes are not merely financial – they are deeply social and humanitarian.
The current instability underscores the importance of transparent, sustainable, and diversified diamond economies, alongside stronger international collaboration, to secure both industry resilience and the livelihoods of millions who depend on it.
The diamond industry has long sought to improve transparency and accountability in how stones are tracked from mine to market. Historically, this relied on paper certificates and manual verification, which were open to forgery, loss, or human error. In recent years, blockchain technology has been introduced as a potential game-changer, offering an immutable digital record of a diamond’s provenance.
From Certificates to Blockchain
Where traditional certificates only provided a snapshot at one point in time, blockchain creates a permanent digital ledger that records every transaction across the supply chain. By using cryptography and decentralisation, platforms like De Beers’ Tracr system provide real-time verification and an unbroken chain of custody for participating diamonds.
For newly mined stones, this represents an important step forward in consumer confidence. Every registered diamond receives a unique digital identity, effectively becoming a “digital twin” of the physical gem. As the diamond travels through cutting, polishing, wholesale, and retail, each transfer is logged and verifiable.
The Limitation: 95% of Diamonds Already in Public Hands
However, while blockchain provides strong assurances for newly mined diamonds, it is important to recognise its limits. More than 95% of all natural diamonds ever mined are already in private hands in jewellery, collections, and across secondary markets. These stones, already in circulation, were never registered on blockchain platforms and therefore cannot be retrospectively traced using this technology.
This means the vast majority of diamonds in existence today remain outside blockchain systems. While blockchain strengthens transparency for future production, it does not solve the challenges of verifying provenance for the overwhelming supply of diamonds already circulating globally.
Why This Matters for Consumers
For buyers and sellers in the secondary market, blockchain is not yet a universal solution. Laboratory expertise remains essential in verifying authenticity, grading, and ensuring consumer protection. At DCLA, as the official CIBJO laboratory for Australia, we recognise the critical role of independent certification. Accurate grading and unbiased reporting remain the foundation of consumer trust particularly for stones not captured by blockchain.
The Future of Diamond Transparency
De Beers’ blockchain initiative is a milestone that may eventually become standard practice across the industry. It addresses many historical weaknesses in tracking systems and aligns with modern consumer demand for ethical sourcing. But for now, blockchain is only part of the answer. The larger challenge remains: how to ensure transparency and trust for the diamonds already in circulation, which make up the majority of the world’s natural supply.
At DCLA, we believe blockchain should be seen as a complementary tool not a replacement for independent laboratory grading and certification. Only by combining robust science with innovative digital systems can the diamond industry achieve true transparency.
In the diamond trade, we often speak of a laser inscription as if it is an unbreakable bond between a diamond and its grading certificate. However, anyone with real-world experience whether on the manufacturing floor or in the secondary market knows the truth: inscriptions can be removed, altered, or forged.
Polish the girdle and the inscription disappears. Re-cut the stone and it’s gone entirely. Worse still, an inscription can be duplicated onto a different diamond to mimic an existing report number. This is not speculation; it has happened, and more often than many in the trade care to admit.
Another serious vulnerability occurs after grading. Once a diamond is set into jewellery, nothing prevents a switch from taking place during setting, repair, or even in transit. This risk is not confined to smaller stones high-value diamonds have been switched in exactly this way.
Verification presents its own challenges. Even if the diamond is the original stone graded by the laboratory, the inscription is frequently obscured by the jewellery setting. Accessing it often requires removing the stone a delicate procedure that carries risk to both the stone and the setting. Most grading laboratories, including DCLA, will not remove diamonds from their mountings, and many jewellers are reluctant to attempt it due to the potential for irreversible damage.
Digital records, blockchain entries, and grading reports track the details, but they do not track the actual physical stone. If the diamond is switched but the paperwork remains unchanged, the system still appears to validate it as authentic. This is precisely how sophisticated fraud can go undetected.
Until the industry bridges the gap between the physical diamond and its digital record, laser inscriptions will remain a weak link in the chain of security.
At DCLA, we believe the next step in true physical traceability lies in combining advanced identification technology with secure, tamper-proof verification processes ensuring that a diamond’s identity is as enduring as the stone itself.
South Africa is to sign up to the milestone Luanda Accord, which is funding a global campaign to promote natural diamonds.
It joined the governments of Angola, Botswana, Namibia, Sierra Leone and the Democratic Republic of the Congo, in June in pledging to contribute 1 per cent of the value of their rough sales annually.
But the move was only approved South Africa’s cabinet last week. Minister in the Presidency Khumbudzo Ntshavheni and confirmed the decision on 7 August, committing 1 per cent of the annual revenues generated from rough diamond sales to a global marketing fund led by the Natural Diamond Council (NDC).
South Africa, the world’s sixth biggest diamond producing nation by value, saw sales down by 21 per cent last year amid the global slowdown.
The country’s mining minister mining minister Gwede Mantashe was listed as a signatory to the Luanda Accord in an official communique after the agreement.
But a conflicting Reuters report said South Africa did not actually sign at the time and has only done so now.
The Luanda Accord is seen as a potential turning point for the sector, aiming to rebuild consumer trust and interest in natural diamonds over lab growns, by emphasizing their origin, authenticity, and community impact.
It will highlight the positive economic and social contributions of the natural diamond industry to producing nations and their communities.
Governments of the African diamond producing nations have been joined by the Antwerp World Diamond Centre (AWDC), African Diamond Producers Association, India’s Gem and Jewellery Export Promotion Council (GJEPC) and the Dubai Multi Commodities Centre (DMCC).
Petra Diamonds has announced plans for a major refinancing program – together with a 33 per cent slide in revenue for FY2025.
The UK-based miner, which has recently sold off two of its four diamond mines, is facing substantial financial and operational challenges.
It is proposing an extension of senior secured bank debt and notes due early next year to 2029 and 2030 respectively, together with a $25m rights issue.
The moves are designed to preserve cash, extend debt repayment timelines, and ensure Petra can continue investing in its two remaining core mines – Cullinan and Finsch, both in South Africa.
Petra’s latest sales results, published on the same day (8 August) as its refinancing package, show some positive momentum in the market with like-for-like rough diamond prices from its latest tender, but revenue for Q4 was down 49 per cent year-on-year to $50m.
Revenue for FY2025 was $206m, down 33 per cent year-on-year from $309m and net debt increased to $264m.
“We would once again like to acknowledge the resilience shown by our employees in navigating a very difficult period for the company and the diamond sector as whole,” the company said in its Q4 and FY 2025 Operating Update.
Meanwhile, in its refinancing proposal Petra said: “Petra has, over the past 18 months, been focused on an internal restructuring that has resulted in a simpler and more streamlined business and operating model.
“This has included the sale of the Koffiefontein and Williamson mines, multiple labour restructuring initiatives and an optimisation and smoothing of the group’s capital development profiles.”
Indian jewelry retailer Tanishq is introducing in-store diamond evaluation some of its 500-plus outlets, as part of an ongoing partnership with de Beers.
Customers will be able to see proof that the diamond they’re buying is natural rather than lab grown, thanks to the De Beers SynthDetect machine, which works with loose and mounted stones.
They can also have diamonds tested with Lightscope, which measures light performance, and with other equipment for performance, inclusions, and laser markings.
Tanishq, part of the Titan group, says the launch of its Diamonds Expertise Centres is designed to give customers greater peace of mind by presenting complex gemological data as simple, visual insights. It says the centers are a “first of a kind initiative”.
The first three are in Bengaluru, but the company plans to expand them to 200 stores this year and eventually to all its outlets.
Ajoy Chawla, CEO at Tanishq, said: “Our aim is to set a new standard in natural diamond retail — one that goes beyond traditional display and transforms the buying journey into a transparent, educational, and truly immersive experience.”
Last August Tanishq and De Beers jointly announced that they’d be working together to promote natural diamonds in India, now the world’s second biggest diamond market.
The partnership leverages Tanishq’s retail presence and De Beers’ expertise and proprietary diamond verification technology.
US President Donald Trump today (6 August) doubled the tariff on all imports from India to 50 per cent, as a punishment for its oil purchases from Russia.
India’s diamond industry, already reeling from confirmation last week of a 25 per cent reciprocal tariff, is in shock that their goods will be subject to a second 25 per cent surcharge.
“I find that the Government of India is currently directly or indirectly importing Russian Federation oil,” Trump said in an executive order.
“Accordingly, and as consistent with applicable law, articles of India imported into the customs territory of the United States shall be subject to an additional ad valorem rate of duty of 25 per cent.”
The first 25 per cent tariff comes into force tomorrow (Thursday 7 August) and the new, punitive tariff is applicable three weeks from now, on 27 August.
The US is the single largest destination for Indian diamonds and gems, accounting for nearly $10bn or about 30 per cent of India’s annual gems and jewelry exports.
Industry leaders were already warning of the dire consequences of a 25 per cent tariff. Now they are facing an unprecedented body blow with the introduction of a 50 per cent double-tariff.
India’s Ministry of External Affairs said in a statement today that the tariffs were “unfair, unjustified and unreasonable”.
It defended its Russian oil purchases, saying they were “based on market factors and done with the overall objective of ensuring the energy security of 1.4 billion people of India”.
The US imposition of an extra tariff was, it said, “extremely unfortunate”.
