Pink Diamonds Erupted to Earth’s Surface after Early Supercontinent’s Breakup

Western Australia’s Argyle mine was among nature’s preeminent treasure troves for nearly 40 years. At its peak, Argyle produced more coloured diamonds than anywhere else on Earth and earned an especially sparkling reputation for its unparalleled cache of pink diamonds.

Researchers have spent decades trying to unravel the origins of Argyle’s glimmering gems. Now, by dating minerals in the mine’s volcanic rock, scientists think they may have finally pieced together the process that created the deposit around 1.3 billion years ago. In a paper published on Tuesday in Nature Communications, the team posits that the breakup of an early supercontinent lifted Argyle’s salmon-coloured stones from crushing depths toward Earth’s surface.

Located 2,200 kilometers northeast of Perth, Australia, in the country’s rugged Kimberley region, Argyle mine once covered an area the size of 94 football fields. Between its opening in 1983 and closure in 2020, when mining the gems there was no longer economically viable, Argyle produced more than 865 million carats of rough diamonds. Most of these stones come in pale shades of yellow or brown. But a small percentage of the site’s diamonds radiate rich pinks, purples or reds. More than 90 percent of the world’s pink diamond supply including the nearly 13 carat Pink Jubilee has come from Argyle.

The pink hue of Argyle’s most lavish diamonds is linked to damage they underwent deep within the earth. According to Hugo Olierook, a geologist at Curtin University in Perth and lead author of the new study, these diamonds start out colourless. But immense tectonic pressure from colliding continents can alter the stones’ crystal structure, unlocking the potential colours hidden within. “The diamonds are being forced to bend and twist,” Olierook says. “If they’re twisted just a little bit, it will turn some of these diamonds pink.” Further twisting makes them become brown.

Argyle’s diamonds took on their pink and brown tints around 1.8 billion years ago, when a piece of what is now western Australia smashed into the northern Australian plate and warped the region’s rock. But this only explains part of Argyle’s origin story. When the continents collided, the area’s diamonds were buried in the mantle, hundreds of kilometers below Earth’s surface. If the crystals had been closer to the surface, their carbon atoms would have been compressed into a different structure, transforming them from shimmering diamonds to lumps of dark gray graphite.

A volcano was necessary to bring the molten diamonds up from our planet’s mantle. “You need some sort of tectonic trigger to bring them up to the surface,” Olierook says. As the melt rises, carbon dioxide and steam expand, sparking an eruption that he compares to popping a champagne cork. At Argyle, this eruption likely occurred at a beach, where sand and seawater interacted with volcanic rock called lamproite.

To determine when the eruption occurred, the team sliced two thin sections of Argyle’s volcanic rock and polished them down to a minuscule width. Analyzing the sample’s mineral makeup under a microscope, the researchers were able to pinpoint sand grains from Argyle’s ancient beach and to date them with the help of radioactive elements they contained. By dating the youngest sand grains, the scientists were able to estimate when the beach was buried in lava. They also used tiny lasers to determine the ages of titanite minerals, which formed in the rock when the magma melded with quartz in the beach sand.

Comparing the ages of the youngest sand grains and the oldest titanite crystals allowed the researchers to estimate that the eruption at Argyle occurred between 1.3 billion and 1.26 billion years ago. This age range was older than previous estimates, which surprised Olierook and his colleagues. “We had a betting pool going, and nobody got 1,300 million years,” he says. “That was one of those glass shattering moments.”

That eruption timing corresponds to a volatile period in Earth’s tectonic history when one of the first supercontinents, called Nuna, was splintering apart. The team posits that this instability may have reopened a seam along the continental boundary where Argyle is now situated. This in turn sparked the volcanic activity that brought the diamond-bearing melt toward the surface, creating Argyle’s expansive diamond deposits.

The new time estimates add crucial context for understanding the volcanic eruption at Argyle, says Evan Smith, a researcher at the Gemological Institute of America, who researches the geology of diamonds but was not involved in the new study. “The previous age constraint for Argyle was younger, and it was a lot less clear how to frame the eruption in a broader geological context,” Smith says. He thinks the new study adds exciting evidence that these “eruptions are related to bigger processes that affect whole continents rather than being isolated, random burps of magma.”

Olierook thinks similar events may have occurred at other continental boundaries around the world. Most diamond-bearing deposits are found in the middle of continental plates where rock is exposed. This makes Argyle an outlier. When the mine was first discovered, most geologists thought that searching for diamonds along continental plate boundaries which are often uplifted by ancient mountain belts and buried beneath soil and sand was futile.

Though gem mining in these regions remains difficult, Olierook believes there are plenty of diamonds to be found in the rough. “I think all of them will host some sort of coloured diamonds,” he says. “They may all be brown, but with a little bit of luck, there could be a few pinks in there.”

Source: Jack Tamisiea Scientificamerican

GIA Lays Off 151 Employees at Carlsbad Headquarters

GIA Lays Off 151 Employees at Carlsbad Headquarters

The Gemological Institute of America (GIA) has cut some 20% of the workforce at its Carlsbad, California, headquarters amid a prolonged slowdown in the industry.

In late July, the lab let 151 employees go, primarily in its laboratory, as well as some in corporate positions, Stephen Morisseau, the GIA’s director of communications, told Rapaport News Sunday. The lab made the layoffs as a result of a drop in the number of diamonds submitted for grading.

“Many organizations in the global gem and jewelry sector are experiencing a downturn due to economic conditions affecting the global gem trade,” Morisseau explained. “Due to those economic conditions, there has been a decline in demand for GIA’s gem identification and grading services, which led to the difficult decision to reduce staffing.”

The layoffs will bring the GIA’s total workforce in Carlsbad to 600, according to The San Diego Union-Tribune, which was the first to report the story. Globally, the lab has approximately 3,500 employees.

“The reductions will not affect our ability to advance our important consumer-protection mission, nor to meet the needs of our clients,” Morisseau added.

Source: Diamonds.net

Diamond prices are in free fall in one key corner of the market

One of the world’s most popular types of rough diamonds has plunged into a pricing free fall, as an increasing number of Americans choose engagement rings made from lab-grown stones instead.

Diamond demand across the board has weakened after the pandemic, as consumers splash out again on travel and experiences, while economic headwinds eat into luxury spending. However, the kinds of stones that go into the cheaper one- or two-carat solitaire bridal rings popular in the US have experienced far sharper price drops than the rest of the market.

The reason, according to industry insiders, is soaring demand for lab-grown stones. The synthetic diamond industry has paid special attention to this category, where consumers are especially price-sensitive, and the efforts are now paying off in the world’s biggest diamond buyer.

The shift doesn’t mean engagement rings are about to go on deep discount — the impact is limited to the rough-diamond market, an opaque world of miners, merchants and tradespeople that is several steps removed from the price tags in a jewelry store.

However, the scale and speed of the pricing collapse of one of the diamond industry’s most important products has left the market reeling. Now, the question is whether the plunging demand for natural diamonds in this category represents a permanent change, and — crucially — if the inroads made by lab-grown gems will eventually spread to the more expensive diamonds that are typically dominated by Asian buying.

Industry leader De Beers insists the current weakness is a natural downswing in demand, after stuck-at-home shoppers sent prices soaring during the pandemic, with cheaper engagement rings having been particularly vulnerable. The company concedes that there has been some penetration into the category from synthetic stones, but doesn’t see it as a structural shift.

“There has been a little bit of cannibalization. That has happened, I don’t think we should deny that,” said Paul Rowley, who heads De Beers’ diamond trading business. “We see the real issue as a macroeconomic issue.”

Lab-grown diamonds — physically identical stones that can be made in a matter of weeks in a microwave chamber — have long been seen as an existential threat to the natural mining industry, with proponents saying they can offer a cheaper alternative without many of the environmental or social downsides sometimes attached to mined diamonds.

For much of the last decade, the risk remained unrealized, with synthetics eating away at cheaper gift-giving segments but making limited headway otherwise. That is now changing, with lab-grown products starting to take a much bigger bite of the crucial US bridal market.

De Beers has responded to weakening demand by aggressively cutting prices for the category known as “select makeables” — rough diamonds between 2 and 4 carats that can be cut into stones about half that size when polished, yielding centrepiece diamonds for bridal rings that are high quality, but not flawless.

De Beers has cut prices in the category by more than 40% in the past year, including one cut of more than 15% in July, according to people familiar with the matter.

The one-time monopoly still wields considerable power in the rough diamond market, selling its gems through 10 sales each year in which the buyers — known as sightholders — generally have to accept the price and the quantities offered.

Price drop
De Beers typically reserves aggressive cuts as a last resort, and the scale of the recent price falls for a benchmark product is unprecedented outside of a speculative bubble crash, traders said.

In June 2022, De Beers was charging about $1,400 a carat for the select makeable diamonds. By July this year, that had dropped to about $850 a carat. And there may be more room to fall: the diamonds are still 10% more expensive than in the “secondary” market, where traders and manufacturers sell among themselves.

De Beers declined to comment on its diamond pricing.

One of the clearest signs of the traction being made by lab-grown diamonds is their share of diamond exports from India, where about 90% of global supply is cut and polished. Lab-grown accounted for about 9% of diamond exports from the country in June, compared with about 1% five years ago. Given the steep discount that they sell for, that means about 25% to 35% of volume is now lab-grown, according to Liberum Capital Markets.

The impact on De Beers was clear in the first half. The Anglo American Plc’s unit’s first half profits plunged more than 60% to just $347 million, with its average selling price falling from $213 per carat to $163 per carat. Its August sale was the smallest of the year so far.

De Beers has responded by giving its buyers additional flexibility. It’s allowed them to defer contracted purchases for the rest of the year of up to 50% of the diamonds bigger than 1 carat, according to people familiar with the situation.

While lab-grown diamonds are currently hurting demand for natural stones, the upstart industry is also suffering. The price of synthetic diamonds has plunged even more steeply than that of natural stones, and are selling at a bigger discount than ever before.

About five years ago, lab-grown gems sold at about a 20% discount to natural diamonds, but that has now blown out to around 80% as the retailers push them at increasingly lower prices and the cost of making them falls. The price of polished stones in the wholesale market has fallen by more than half this year alone.

De Beers started selling its own lab-grown diamonds in 2018 at a steep discount to the going price, in an attempt to differentiate between the two categories. The company expects lab-grown prices to continue to tumble, in what it sees as a tsunami of more supply coming onto the market, Rowley said. That should create an even bigger delta in prices between natural diamonds and lab-grown, helping differentiate the two products, he said.

“With the increase in supply we’ll see prices fall through the price point and reach a level where, long term, it does not compete with bridal because it comes too cheap,” said Rowley. “Ultimately they are different products and the finite and rarity of natural diamonds is a different proposition.”

Reporting by Thomas Biesheuvel Mining.com

China’s Gold Economy: Consumer desire for gold increases, desire for diamonds decreases

In the first half of this year, China consumed nearly 555 tons of gold, up more than 16 percent year-on-year. The trend has been described as a domestic gold craze. But diamonds seem to have lost their attraction, as the market size in China declined to 11.4 billion U.S. dollars in 2022, 2.5 billion dollars less than in 2021. Xu Hua has more from the southern Chinese city of Shenzhen, China’s biggest distribution center for wholesale jewelry.

XU HUA Shenzhen Shuibei Jewelry Market “We’re at Shenzhen’s Shuibei Jewelry Market, the biggest wholesale market of its kind in China. The market has been crowded with consumers from all over the country for months, as international gold prices continue to rise. Let’s go and see what the best seller is here.”

The hustle and bustle of the Shuibei Jewelry Market since the beginning of 2023 marked a strong comeback from last year. With attractive designs, diverse styles and low prices, dozens of deals can be reached in seconds.

YU WANLING Shenzhen Resident “Shuibei is well-known for its gold sales. The quality gold is more reassuring than other places.”

ZHENG CE Shenzhen Resident “We are about to get married. We prefer to buy some gold rather than diamonds for inheritance or for wearing.”

China’s domestic consumption of gold jewelry reached 555 tons in the first half of 2023. Among the gold consumption, the purchase of gold bars jumped 30 percent year-on-year to 146 tons, while that of gold jewelry reached 368 tons, up almost 15 percent from the same period last year.

HAO RUNSONG General Manager, Lidu Gold “In 2023, our gold sales increased by 20-30 percent compared with last year.”

By contrast, the doorways of neighboring diamond stores looked relatively lonely, as the precious gems lost some significant value over the last few months.

LIU JINGLI Manager, Yishidai Jewelry “The retail transaction volume of diamond inlays is relatively low, and the wholesale sales of our diamond inlays is also declining.”

ZHAO LI Director, The Gold Plaza Operation Center “The sales of diamond jewelry have declined slightly, partly due to falling prices, fewer marriages, the impact of cultivated diamonds, and changing buyer behaviour.”

For daily social needs, some consumers looked to art jewelry as an alternative to diamond jewelry.

HUANG WEIJUN Brand Director, Shenzhen REIEN Jewelry “Our sales of art jewelry in the first half of this year have increased by about 300 percent over the whole of last year.”

Some economists say the booming gold sales are a direct reflection of a gloomy economic outlook.

WU HAIFENG Executive Director, Shenzhen Institute of Data Economy “When people feel uncertainty about the future, especially on the economy, especially about the income growth, people will think to change their investments platform from a variety of the financial products to hard currencies such as gold, such as real estate.”

However, Wu says that the real estate market hasn’t looked good since the beginning of the last year, so Chinese consumers and investors have been looking at other products. Wu added proper stimulative policies are still needed to ensure a healthy market and economic rebound. Xu Hua, CGTN, Shenzhen, Guangdong Province.

Slower Growth for Fancy Colour Diamond Prices

Fancy colour diamonds saw slower growth in the last three months, with an increase of just 0.5 per cent in the FCRF Index, which tracks prices across all colours, sizes and intensities.

That compares with a 1.3 per cent rise during the first quarter of 2023, as reported by the New York-based Fancy Colour Research Foundation, with the biggest increases among yellows.

During Q2, yellows diamonds again drove the increase, with a rise of 6.5 per cent across all categories. Pinks were up 0.2 per cent and blues rose by 0.6 per cent.

The FCRF noted that fancy colour diamonds had again out-performed white diamonds, which saw prices fall 3.5 per cent during the quarter.

Board member Eden Rachminov said: “The first six months of 2023 were intriguing. We experienced notable spikes in certain sub-categories within the yellow category, particularly in the intense and vivid grades with a high inner-grade.

“Meanwhile, the blue and pink categories remained stable. If the world economy continues to maintain its positive momentum, we can anticipate a robust price behavior after the summer.”

The FCRF tracks pricing data for fancy colour diamonds in Hong Kong, New York, Geneva and Tel Aviv.

Source: IDEX

How accurate are jewellery valuations?

The accuracy of jewellery valuations can vary depending on several factors. Here are some key points to consider:

  1. Appraiser’s expertise: The accuracy of a jewellery valuation depends on the competence and experience of the appraiser. A certified gemologist or a professional jewellery appraiser with relevant credentials is more likely to provide a precise and reliable valuation.
  2. Purpose of the valuation: The purpose of the valuation matters. If the valuation is for insurance coverage, it may be higher to ensure full replacement in case of loss or theft. If it’s for resale, the value may be lower as it accounts for market conditions and potential profit margins for a buyer.
  3. Quality of the jewellery: The quality of the jewellery, including the materials, gemstones, craftsmanship, and overall design, plays a significant role in its valuation. High-quality materials and precious gemstones will generally have higher values.
  4. Market conditions: The fluctuating prices of precious metals and gemstones can impact the accuracy of a jewellery valuation. Market conditions change over time, so a valuation today might not hold the same value in the future.
  5. Certification and documentation: Having proper documentation and certifications for gemstones and metals enhances the accuracy of the valuation. This information helps appraisers make more precise assessments.
  6. Appraisal method: There are different methods for valuing jewellery, such as comparison with similar pieces, the cost to replace, or the intrinsic value of materials. Each method has its advantages and limitations.
  7. Local market differences: Valuations can vary across different regions due to variations in consumer preferences and market demands.

It’s important to note that a jewellery appraisal is an expert’s opinion based on their evaluation of the item at a particular point in time. The value assigned to the jewellery may change over time due to various factors, including market fluctuations, changes in demand, or updates in gemstone grading techniques.

AcuVal Adds the consistency of repeatable outcome, this give you a credible and trusted valuation.

555 carat Diamond Bought with Illicit Funds, SEC Says

Cryptocurrency mogul Richard Heart allegedly used proceeds from the sale of unregistered securities to buy the 555-carat Enigma diamond, according to the US Securities and Exchange Commission (SEC).

The SEC has charged Heart — who was born Richard Schueler and who created the Hex cryptocurrency token — with selling the securities to raise more than $1 billion from investors. It alleges that Heart and his PulseChain company committed fraud by misappropriating at least $12 million of those funds to purchase luxury items, including sports cars, watches and the diamond.

“Heart called on investors to buy crypto asset securities in offerings that he failed to register,” Eric Werner, director of the SEC’s Fort Worth regional office, said in a statement Monday. “He then defrauded those investors by spending some of their crypto assets on exorbitant luxury goods.”

The Enigma, which is believed to have come from outer space, is the largest faceted diamond of any kind to appear at auction. Heart purchased it from Sotheby’s at a one-off sale in February 2022 for GBP 3.2 million ($4.3 million). At the time, Heart tweeted that he had bought the stone and would rename it the Hex.com diamond as a nod to his cryptocurrency platform, calling it a “match made in heaven.” Hex has a “5555 day club” comprising people who hold 5,555-day Hex stakes — the longest possible stake in the electronic token.

Sotheby’s, which accepted payment for the Enigma, was not mentioned as a defendant in the SEC’s lawsuit.

“Sotheby’s does not comment on individual transactions, but we can confirm we have established due diligence procedures, tailored and updated to take account of our requirements to conduct business in compliance with applicable laws and regulations,” the auction house stated.

Source: Diamonds.net

30ct. Pink Diamond Garners Record Sum for Tender House

A 29.52-carat pink diamond went for more than $8 million at South Africa-based Pioneer Diamond Tender House, the highest price for any stone the company has sold.

The fancy-vivid-pink, type II rough — named the Protea Pink after South Africa’s national flower of the same color — raked in $271,307 per carat, Pioneer said Wednesday.

A junior mining company recovered the diamond from a deposit on the banks of the middle Orange River, according to Lyndon de Meillon, a shareholder in Pioneer. The stone is believed to come from a 90 million-year-old Lesotho kimberlite that broke off and made its way down the river, where it got trapped in a terrace approximately 500 kilometers from its original location, he explained.

“This unique diamond…once again showcased why the alluvial diamond deposits of South Africa represent the highest and most consistent value-per-carat diamond supply in the world,” de Meillon added.

Source: rapaport

Junior miner recovers spectacular pink diamond from banks of Middle Orange River

JOHANNESBURG- A junior diamond mining company has recovered a spectacular pink diamond from the banks of the Middle Orange River.

The diamond, named Protea Pink, is a fancy pink, 29.52 ct type II diamond, with unusual depth of colour and exceptional clarity. Its colour is reminiscent of the pink hues found in South Africa’s national flower, the protea.

This diamond was most likely derived from the 90-million-year-old Lesotho kimberlites and made a remarkable journey down the Orange river to be trapped in an ancient river terrace, approximately 500 km from its source, South African Diamond Producers Organisation (Sadpo) vice-chairperson and geologist Lyndon de Meillon stated in a release to Mining Weekly.

Sadpo, an organisation that aims to streamline the diamond diggers industry, is headed by CEO Yamkela Makupula, who is a director of Pioneer Tender House, where Protea Pink will be sold on tender in South Africa during the week of 26/30 June. The sale will end on Friday 30 June.

The Middle Orange River, which is known as the area with the highest average value per carat in the world, also has the lowest grade in carat per hundred tonnes of any area actively mined, De Meillon explained.

The modern-day alluvial diamond miner utilises no chemicals in the recovery process and rehabilitation of the mining areas has been proven to improve the carrying capacity of the land, De Meillon added.

Unemployment rates in the area are alarmingly high, exceeding 70%, with mining operations, such as this one by a junior miner, playing a crucial role in supporting the local economy by providing job opportunities and stimulating economic growth.

The revenue generated from diamond mining can contribute to infrastructure development, education, healthcare, and other essential services in the community.

Source: miningweekly

De Beers Sales Slide as Slow Trading Continues

De Beers’ sales value fell this month as global rough demand weakened and the miner reduced prices of its larger stones.

Proceeds dropped 32% year on year to $450 million at 2023’s fifth sales cycle from $657 million in the equivalent period a year earlier, De Beers reported Wednesday. Sales declined 6% compared with the $479 million that the fourth cycle brought in. The total included the June sight as well as auction sales.

“Following the JCK [Las Vegas] show, and with ongoing global macroeconomic challenges continuing to impact end-client sentiment, the diamond industry remains cautious heading into summer,” said De Beers CEO Al Cook. “Reflecting this, we saw demand for De Beers rough diamonds during the fifth sales cycle of the year slightly softer than in the fourth cycle.”

De Beers lowered prices at the sight by 5% to 10% mainly in 2-carat categories and larger, as well as for some 1- to 1.5-carat items, market insiders said. It also extended its buyback program, which allows sightholders to sell goods back to the miner following the purchase.

This reflected weakness in the rough that produces polished above 0.30 carats, and especially the stones that yield 1-carat finished diamonds. These sizes are especially weak in the US market amid economic uncertainty and a lull in engagements, dealers explained. Rough under 0.75 carats has seen a mild recovery as Indian manufacturers look to fill their factories with low-cost material.

Source: rapaport.com