watch – The Diamond Certification Laboratory of Australia (DCLA)

Why Diamond Grades Can Differ Between Laboratories: Understanding Colour and Clarity Variations

GIA (Gemological Institute of America) and DCLA (Diamond Certification Laboratory of Australia)

Why Diamond Grades Can Differ Between GIA and DCLA: Understanding Colour and Clarity Variations

The difference in diamond grading between laboratories like GIA (Gemological Institute of America) and DCLA (Diamond Certification Laboratory of Australia) can occur due to the subjective nature of diamond grading and variations in grading standards, tools, and methodology.

Here’s a detailed explanation of why this happens:

Example of a diamond graded GIA E VS2 vs DCLA F SI1:

1. Grading is Subjective to Some Extent

Even though labs follow international grading systems like those defined by CIBJO or GIA, colour and clarity grading involves human judgment under magnification and controlled lighting conditions. Two experienced graders may interpret borderline characteristics differently.

Colour: E and F are adjacent grades, and the difference is extremely subtle—often imperceptible to the untrained eye.
Clarity: The distinction between VS2 (Very Slightly Included 2) and SI1 (Slightly Included 1) can also hinge on size, position, nature, and number of inclusions, which may be judged differently by separate labs.

2. Different Lab Philosophies

GIA is widely considered the global benchmark for consistency and tends to be more conservative in some grading aspects, especially in colour.
DCLA, while highly respected and CIBJO-accredited (and Australia’s official diamond authority), might interpret certain characteristics differently based on their internal grading protocols.

3. Grading Conditions and Equipment

Minor differences in:

Lighting
Magnification tools
Grading environments
can affect the appearance of a diamond, especially in borderline cases.

4. Grading Date and Re-evaluation

Grading can differ if:

The diamond was graded at different times.
The diamond was repolished or slightly recut between submissions.
The grader has different levels of training or experience (even within the same lab over time).

5. Lab-to-Lab Variance Is a Known Industry Factor

Even among top labs (GIA, IGI, HRD, AGS, DCLA), 1-grade differences in colour or clarity are common and not considered errors. This is why many dealers and appraisers say a difference of one colour or clarity grade is within acceptable tolerance.

In Your Example:

GIA E VS2 vs DCLA F SI1:
- The colour difference (E vs F): within acceptable tolerance; both are considered colourless.
- The clarity difference (VS2 vs SI1): SI1 is a full grade lower, but this could be due to:
  - An inclusion judged more impactful by DCLA
  - A stricter application of clarity grading by DCLA
  - GIA possibly being more lenient on that particular clarity characteristic

Differences like GIA E VS2 and DCLA F SI1 can result from:

Subjective human interpretation
Slightly different grading standards
Borderline characteristics
Environmental and technical grading factors

For buyers or sellers, it’s important to:

Always compare certificates from top-tier labs.
Understand that 1-grade discrepancies are common.
Consider getting a professional review if there’s a significant value implication.

Graff Opens Huge Store in Las Vegas

Graff has opened its biggest store in North America, at the Fontainebleau Las Vegas luxury resort and casino.

The 3,300sq ft showroom is second only to the flagship Graff in Paris, at 3,700sq ft.

Graff, founded in 1960 by British jeweler Laurence Graff, is recognized as one of the world’s most prestigious luxury jewelers.

CEO Francois Graff (Laurence’s son) said: “The opening of our new salon at Fontainebleau Las Vegas represents a pivotal moment for Graff in North America, a testament to our continued success and commitment to expansion across the region.”

The Las Vegas store is the brand’s 10th location in North America. It has more than 50 worldwide.

The new showroom features a serpentine counter with angular displays inspired by diamond facets, a bespoke bridal area with engagement rings, wedding bands, and bridal jewelry crafted from celadon wood and chiseled glass.

To celebrate the opening, Graff has curated a special selection of high jewelry featuring rare diamonds, emeralds, rubies, and sapphires.

Source: IDEX

35 ct Kashmir Sapphire sets World Record

A 35.09-carat sapphire yesterday set a new world record for the highest per-carat price paid at auction.

The Regent Kashmir sold for HKD 74.7m (USD 9.6m), equivalent to USD 271,515 per carat, at Christie’s Hong Kong.

The same gem also set a record back in 2015, when it was sold at Christie’s Geneva for USD 7.4m, equivalent to $209,689 per carat.

That record was broken the same year by another sapphire, the 27.6- carat Jewel of Kashmir, which sold for $6.7m at Sotheby’s Hong Kong in 2015, equivalent to USD 243,703 per carat.

But the record now reverts to gem known as the Regent Kashmir, an antique cushion-shaped, unheated, royal blue sapphire set in a platinum ring with round diamonds.

“The Regent Kashmir sapphire’s record-breaking price of $271,515 per carat with a total price of $9.5m, is a landmark moment for the sapphire market – proof that the rarest gems still command unstoppable power,” said Tobias Kormind, MD and co-founder of online jeweler 77 Diamonds.

“Gemstones of this calibre continue to be sought after and go up in value.”

The sapphire sold above its low estimate (HKD 65m, USD 8.3m) but didn’t reach its high estimate (HKD 95m, USD 12.1m).

Source: IDEX

3 ct Pink Diamond could Fetch $1.6m

A fancy intense 3.03-carat pink diamond is among the highlights at Phillips’ New York Jewels Auction next month with a $1.2m to $1.6m estimate.

Other diamonds of note include a 4.43-carat oval fancy vivid yellow diamond ring (estimate $75,000 to $125,000), and a colorless emerald-cut diamond weighing 6.03 carats (F color, VVS1 clarity) with a $90,000 to $150,000 estimate. All three diamonds are set in rings.

The sale also features Etoile de Mer, a starfish-shaped sapphire, tsavorite, and diamond brooch by Jean Schlumberger, the French jewelry designer who famously revitalized Tiffany & Co during his tenure there, from 1956.

Among the 105 lots there is also a selection of signed jewels from Van Cleef & Arpels, Bulgari, Chaumet, and others. The sale is on 12 June.

Source: IDEX

392 ct Blue Belle Sapphire could Fetch $12m

The Blue Belle sapphire and diamond necklace is to lead a Christie’s New York sale next month with an estimate of $8m to $12m.

The tassel pendant features a 392.52 carat unheated, cushion modified, mixed-cut sapphire from the famed Ratnapura region of Sri Lanka, together with oval-shaped diamond terminals, and a brilliant-cut diamond neckchain, mounted in gold.

The estimate is well below the $17.6m the piece sold for at Christie’s Geneva when it last changed hands in November 2014.

The sapphire was recovered in 1926 and was sold in 1937 to was sold to British motor magnate Lord Nuffield, founder of Morris Motors.

There were reports at the time that the gem would be gifted to HM Queen Elizabeth the Queen Mother on her coronation day, though this didn’t actually happen.

“Sapphires of this caliber are extraordinarily rare,” said Rahul Kadakia, Christie’s international head of jewelry.

“This remarkable stone must be considered among the most prestigious colored gemstones to appear on the market in many years – truly worthy of any world-class collection.

Among other highlights at the Magnificent Jewels live auction on 17 June, is the Marie-Thérèse Pink Diamond, 10.38-carat kite-shaped fancy purple-pink diamond that is said to have belonged to Marie Antoinette.

It has recently been set into a contemporary ring by the Parisian jeweler Joel Arthur Rosenthal

Source: IDEX

Lucapa Diamond Company Enters Voluntary Administration Amid Market Pressures

Lucapa Diamond Company has entered voluntary administration following a major cost-cutting initiative and a significant reduction in its corporate workforce. The decision comes in the wake of mounting financial pressure and weakening global diamond demand, attributed in part to US President Donald Trump’s trade tariffs, which have disrupted pricing and buyer confidence.

KordaMentha Appointed as Administrators

Leading corporate recovery firm KordaMentha Restructuring has been appointed to oversee Lucapa’s administration, with Richard Tucker and Paul Pracilio named as voluntary administrators. Their immediate focus is an urgent operational and financial assessment of Lucapa, followed by a dual-track recapitalisation and potential sale process.

Lucapa’s Key Assets: Lulo and Merlin Projects

Lucapa holds a 40% interest in the high-value Lulo alluvial diamond mine in Angola. The site is known for producing large, premium-quality Type IIa diamonds, including stones exceeding 100 carats.

In Australia, Lucapa’s flagship asset is the Merlin Diamond Project in the Northern Territory. The project includes a 24 km² mining lease and a 210 km² exploration licence. Historically, eight of the 11 known kimberlite pipes at Merlin were mined by Rio Tinto (ASX: RIO) and Ashton Mining between 1999 and 2003, yielding approximately 500,000 carats from 2.2 million tonnes of processed kimberlite.

Financial Challenges in Q1 2025

Lucapa’s March quarter report highlights a sharp downturn in financial performance. Diamond inventories dropped 44% to 1,685 carats, and cash and receivables fell 41% to $2 million. Additionally, the company took on $600,000 in interest-bearing debt during the period. In response, Lucapa implemented a thorough review of its corporate expenditure, resulting in reduced overheads and workforce downsizing.

The company noted that the full impact of US trade tariffs on diamond sales has yet to be determined. However, uncertainty among buyers throughout April has led to softened demand and reduced prices across the industry.

Path Forward Through DOCA

Despite the challenges, there is optimism that Lucapa may recover through a Deed of Company Arrangement (DOCA). KordaMentha’s Richard Tucker previously stated that approximately 99% of mining companies the firm assists successfully emerge from administration via DOCA, which aims to preserve operations and secure better outcomes for creditors than liquidation.

Lucapa Diamond Company’s move into administration reflects broader challenges in the diamond sector, including geopolitical trade tensions and market uncertainty. The success of the upcoming recapitalisation or sale process, under the guidance of KordaMentha, will be critical in determining the company’s future and protecting the value of its premium diamond assets.

Petra Diamonds hits all-time low as cash burn continues

Petra Diamonds is to begin discussions with financiers on refinancing a $273m bond that matures in March next year amid scepticism that the company will survive the event.

The ratings agency S&P last week downgraded the company’s credit to CCC on the increased likelihood of default, and maintained a negative outlook.

Shares in the company fell 10% today shortly after the company posted its third quarter results. Petra is now trading at a fresh all-time low and is valued at only £34m on the London Stock Exchange.

While its remaining two assets – the Cullinan and Finsch mines in South Africa – had a solid three months operationally, with a quarter to go, full year guidance has been maintained at 2.4 to 2.7 million carats.

However, the company is still burning cash.

Petra drew on a further $33m as consolidated net debt increased to $258m as of end-March, which the company put down to working capital requirements.

The truth is that the company is desperately in need of improved diamond prices, which have continued to trough this year amid economic uncertainty generated by US President Donald Trump’s on-off tariff regime.

Petra said in April that it had postponed the sale of about 200,000 carats of diamonds from the Cullinan mine near Pretoria because of the “considerable diamond market uncertainty caused by the US tariffs announcement”.

“S&P believes the company faces mounting liquidity challenges amid uncertainty regarding the recovery of the rough diamond market and approaching debt maturities in 2026, with increased likelihood of default – including distressed exchange or debt restructuring – over the next 12 months, if Petra is unable to refinance its debt maturities on time,” said analysts at Berenberg Bank in a note last week.

Commenting on the third quarter results – in which revenue fell to $42m from $106m in the comparative quarter last year (buoyed by sales from a deferred tender) – interim joint CEOs Vivek Gadodia and Juan Kemp, said Petra had experienced “a very difficult diamond market”.

They added: “We believe the steps we have taken over the past 12 months position Petra well for a successful refinancing. We will now look to commence engagements with our lenders on the refinancing of our debt maturing in early 2026.”

Source:miningmx.com

$28m Emergency Funding as Lucara Sales Dip

Lucara is drawing down up to $28m in emergency funding for its underground mine expansion after reporting a slump in Q1 earnings and lowering its revenue guidance for the full year.

The Vancouver-based miner received lender approval for the funds from its Cost Overrun Reserve Account (CORA) extending a standby undertaking, as it faces increasing financial pressure from declining revenues, operational disruptions, and a weak diamond market.

Revenue for the first quarter slipped 23 per cent to $30.3m, as heavy rainfall in January forced the company to process lower-grade stockpile material at its Karowe open pit mine, in Botswana. It sold 72,871 carats, down 22 per cent year-on-year.

“This lower revenue outlook has led management to assess the company’s ability to continue as a going concern, with concerns raised about sufficient working capital, cash flow from operations, and liquidity to meet obligations and ongoing UGP (underground mine plan) development,” Lucara said in its Q1 2025 Results.

Projected revenue for the full year has been lowered from $195m – $225m to $150m – $160m, although this figure excludes sale of the 2,488-carat Motswedi diamond that was recovered in August 2024.

Petra said lenders had approved a draw of up to $28m from the cost overrun reserve account to allow work on the underground expansion to continue.

In exchange, Nemesia, its largest shareholder, agreed to extend its shareholder standby undertaking until the project is finished.

During Q1 Lucara said it recovered six stones over 100 carats including the a 1,476 carat non-gem diamond that was sold on tender for $1.11m.

Source: IDEX

Al Capone’s Diamond-Studded Patek Philippe Pocket Watch Heads to Sotheby’s Auction

Al Capone’s Diamond-Encrusted Pocket Watch to Be Auctioned at Sotheby’s

A dazzling piece of underworld history is heading to auction: Al Capone’s custom diamond-studded pocket watch, crafted from platinum and set with 90 diamonds, will go under the hammer at Sotheby’s next month. The extraordinary Patek Philippe timepiece, dripping in gangster-era flair and opulence, is expected to fetch between USD $80,000 and $160,000.

Nearly a century before “bust-down” watches became a mainstay in hip-hop culture, Capone was already setting trends. Dissatisfied with the understated design of his factory-made Patek Philippe, the infamous Chicago mob boss commissioned a local jeweller to completely rework it. The result? A solid platinum case housing the original movement, with a striking caseback spelling out “AC” in 90 single-cut diamonds—a bold, custom feature unheard of at the time.

“This type of gem-setting would have been extremely rare during that period,” says Geoff Hess, Sotheby’s Global Head of Watches. “Capone wasn’t just ahead of his time as a criminal—he was ahead of his time in style.”

This is not the first time Capone’s lavish timepiece has appeared at auction. In 2021, it was sold alongside other personal items—including his diamond tie bar and favourite Colt .45 pistol—by his descendants through Witherells, a California-based auction house. Estimated at $25,000 to $50,000, the watch far exceeded expectations, fetching $229,900.

While the dial shows signs of age and the minute hand is missing, the watch remains a compelling piece of Americana. It’s less a horological grail than a conversation-starting symbol of 20th-century notoriety and excess. Today, collectors tend to frown upon aftermarket diamonds, especially in vintage watches—but this piece is a bold exception. Capone’s customised pocket watch stands as a testament to his legacy: extravagant, defiant, and unmistakably iconic.

Graff and Moussaieff in UK Rich List

Laurence Graff and his son Francois are ranked 44th in the newly-published Sunday Times Rich List 2025 of Britain’s 350 wealthiest individuals.

Their worth is estimated at £3.65bn ($4.85bn), up £50m ($66m) on last year’s figure.

Laurence Graff founded the iconic Graff Diamonds in 1960 and remains chairman, aged 86. Francois, who has been involved in the family business for over 35 years, now serves as CEO.

Also in the Rich List, at number 342, is Alisa Moussaieff and family, with an estimated £342m ($454m) worth.

She is the CEO and creative director of the exclusive Moussaieff Jewellers, founded by her late husband Shlomo in 1963.

Top of the list is Gopi Hinduja and family. He chairs the Hinduja Group, a multinational conglomerate spanning automotive, oil and speciality chemicals, banking and finance, IT, cybersecurity, healthcare, trading, infrastructure project development, media and entertainment, power, and real estate, valued at £35.3bn ($46.9bn).

King Charles II is at 238, with £640m ($851m).

Source: IDEX