diamond colour – The Diamond Certification Laboratory of Australia (DCLA)

Buying a Diamond explained Cut, Colour, Clarity & Carat

When it comes to buying that dream diamond, most people are unsure of what to look for. Buying that perfect diamond is not a low-cost exercise, with an average selling price of $16,000 for a 1 Carat quality diamond ring. Making sure that you make the correct choice for your budget is vital in making any diamond purchase.

Here are some tips from Australia’s diamond experts at the DCLA.

The Diamond Shape:
The shape is the first and most important decision to make when purchasing a diamond as this sets the design of your jewellery piece. The diamond shape sometimes referred to as cut, is the geometric appearance of the stone. The shapes are categorised into two groups for pricing, round diamonds, and fancy shape diamonds.

Round Diamonds
Round brilliant cut diamonds are the most traditional and popular diamond shape consisting of 57 facets top and bottom. Almost 75% of all manufactured diamonds are round.

The diamond shape is 100% symmetrical when polished and having an excellent grade will display a range of features helping the crystal reflect light.

Round diamonds are the only shape that has a proven proportion or cut grade, which shows the optimum angle for a diamond to return the right amount of light back to the viewer.

This grade is based on light tracing. This is the way light refracts through the crystal, then reflecting off the facets and returning to the table and crown.

Fancy Shape Diamonds
Fancy shape diamonds refer to all diamonds other than the round brilliant shape.

These include the traditional shapes like pear, emerald, oval, marquise, cushion, heart and asscher. As well as the newer modern cuts like the princess, trilliant and radiant.

The modern fancies have become popular with cuts like the square radiant and Princess have remarkably high light return due to symmetry, facet design and placement.
These stones have similar brilliance to the round due to faceting. Facets start at the girdle (outer rim of the stone) and run down to the culet (point at the bottom).

The step cuts like emerald shape diamond are traditional as the facets run parallel to the table. These facets to create clean optical appearance.

As the step cut diamonds are less brilliant, small inclusions can sometimes be visible. To avoid visible inclusions step cuts diamond need to be of higher clarity grades, especially with centrally located high contrasting inclusions.

Fancy shapes with longer length to width ratios like marquise or pear, give a slimming effect when set correctly down the finger. The unique look of the longer stones. Oval, marquise, and pear-shaped diamond makes it a popular choice.

The square cushion shape cut in the brilliant style, has the same properties as the round brilliant and if cut with 8 main top and bottom corresponding corners (main facets) will have the Hearts and Arrows effect.

The cushion shape stone has rounded corners which make it a great alternative to a round at a lower price per carat the other of the 4C’s being equal. (Carat, Colour, Clarity).

All diamonds are unique just like you. The 4Cs Colour, Clarity, Cut and Carat weight along with many other more subtitle characteristics give the diamond its grade and set the stones value. Diamonds with the same 4C’s grade can be quite different in value due to the more subtle characteristics mostly overlooked when buying. Understanding the 4Cs along with these characteristics is a very important step in purchasing your perfect diamond.

The Diamonds Cut
The cut refers not to the shape (e.g., round, oval etc.) but to a diamond’s proportions, symmetry, and polish. The beauty of a diamond depends more on cut than any other factor as it determines how light travels into the stone and is returned to the viewer.

The cut of the diamond is arguably the most important of the 4Cs as it directly impacts the diamonds light performance. A diamonds facets are designed and placed in varied orientations and specific angles to reflect the light in a uniform way. Like tiny mirrors, each facet is precisely polished and arranged to maximize its reflective properties.
A master diamond cutter will be trained to get the most weight from the rough diamond, while getting the best light performance from the diamond crystal. This is a delicate balance not always achieved, as such the diamond proportion or cut quality should be the highest priority.

When a diamond proportion or cut grade is low, the diamond performance will let down even the highs colour and clarity. A lower colour diamond with an Excellent proportion grade will have better brilliance and fire and look better than a high colour with a good proportion.

Here are some useful terms when referring to a diamond cut:

Proportion or cut grade is precision and angle of the diamond faceting.
Symmetry is the mirror image of the stone referenced like a clock 12 – 6 and 9 – 3 as well as alignment of the facets top to bottom.
Polish is the overall finish of the skin or surface of the diamond. This includes features or characteristics like surface graining, naturals, or extra facets.

Diamond Colour
Diamonds come in every imaginable colour from pure white to any other colour in the spectrum. Many coloured diamonds are highly prized, however the presence of yellow tint in a white diamond with greatly reduce its value.

Diamonds are graded on a scale from D (colourless) through Z (light colour). D-Z are considered white (cape scale) and true fancy coloured diamonds (such as pink or blues) are graded on a separate scale.

Colour is accurately judged when viewed in laboratory conditions against a known comparison stone which are called a master set. Diamond colour distinction is so subtle that it is practically invisible to even the trained eye.
White diamonds or Cape series have formed from a carbon nitrogen bond and the more nitrogen the more yellow is visible. Very rare and completely colourless diamonds have no nitrogen and are known as type 2a. These are the most valuable.

Diamond Clarity
Diamond clarity refers to the diamond’s inclusions. Inclusions come in many variants from solid carbon to clouds or remnants of microscopic fractures all formed in the diamond billions of years ago.

The more inclusions or the larger the inclusion the lower the clarity grade. These can sometimes cause transparency issues or interrupt the refraction of light, affecting its brilliance. Most diamonds have inclusions, very few are internally flawless or pure.

Diamonds are graded for clarity on a scale that runs from IF (internally flawless) to I (included). The higher the grade, the clearer the diamond, with fewer inclusions and a more perfect appearance. The diamond clarity scale has six categories, with 11 specific grades.

Flawless (FL): There are no inclusions or blemishes visible to the diamond under 10x magnification.
Internally Flawless (IF) Loupe Clean: There no inclusions visible to the diamond under 10x magnification there may be external characteristics.
Very Very Slight Inclusions (VVS1 and VVS2): Inclusions of 5 – 10 microns or a number of smaller cloud like inclusions. Very difficult for a skilled grader to see under 10x magnification.
Very Slight Included (VS1 and VS2): Inclusions are found by experienced grades under 10x magnification, characterised as minor.
Slightly Included (SI1 and SI2): Inclusions are easily found under 10x magnification, buy not eye visible.
Included (I1, I2 and I3): Inclusions sometimes visible to the naked eye are easily found under 10x magnification. These inclusions may affect the transparency and brilliance of the diamond.

Diamond Carat
Carat or weight is the biggest contribution to the value of the diamond but is only one part in determining the value of a diamond. That said all else being equal IE: the cut, colour and clarity, a diamond’s price does increase with every size category in carat.

Rarity also determines the value of the diamond with larger stones being rarer and more valuable.
A diamond carat is the actual measured weight of the stone and due to different proportion grades, this is necessarily an indication of its size.

Dominion Diamond unveils plan to avoid bankruptcy

Canada’s Dominion Diamond Mines has unveiled a transaction that would allow it to exit court protection from creditors and access short-term operating funds, which would pave the way to eventually restart its idled Ekati mine in Canada’s Northwest Territories.

The company, which owns and operates the iconic Ekati diamond mine and also has a 40% interest in the nearby Diavik, said it had signed a letter of intent with an affiliate of The Washington Companies.

The privately held Montana-based conglomerate bought Dominion for $1.2 billion in 2017 when the miner was the world’s third-largest producer of rough diamonds by value.

Under the agreement, which requires court approval, Washington would buy the company’s assets for about $177 million, while assuming its operating liabilities.

It would also provide Dominion with up to $84 million in short-term debtor-in-possession financing.

Ekati has been halted since March to help slow down the spread of the coronavirus pandemic. The operation was left with about $180 million worth of inventory, which it has been unable to sell since its Belgian retailers remain closed.

The diamond miner said at the time that covid-19 had a “devastating impact” on the global diamond mining industry, affecting the company.

According to court documents seeking bankruptcy protection from creditors, Dominion revenue from diamond sales last year reached about $528 million.

The company said the proposed sale would be conditional on reaching an agreement with Rio Tinto on the Diavik joint venture. Failing that, Dominion would exclude its interest in the Yellowknife diamond mine from the transaction.

The miner is a major employer in the Northwest Territories, with 634 workers, 60% of whom are locals. Only 212 people are currently at the mines, which are fly-in and fly-out operations. This allows for a pre-screening of the staff before they are allowed to board flights to Ekati and Diavik.

Shattered dreams

The global coronavirus outbreak squashed diamond miners’ dawning hopes of a recovery in a sector already reeling from weak prices and demand since late 2018.

De Beers, the world’s largest producer by value, cut 2020 production guidance by a fifth last month after earlier cancelling its April sales event.

Russia’s Alrosa, the world’s top diamond producer by output, saw sales for rough and polished diamonds drop to $15.6 million. The figure stood in stark contrast to the $152.8 million the diamond miner fetched in March and the $405 million in January.

Lucara Diamond, another Canadian company, posted earlier this month a net loss of $3.2 million, or $0.01 a share, for the first three months of the year.

The figure was in sharp contrast with the $7.4 million in net income, or $0.02 in earning per share the miner reported in the same period last year.

South Africa’s Petra Diamonds recently delayed interest payments to borrow $21 million in new debt, a crucial move to keep the company afloat.

Investment banks are increasingly reluctant to extend credit to diamond producers, as inventory is not being sold and defaults are possible, analysts have warned.

“We are concerned about an oversupply of rough diamonds following the reopening of economies, as a lot of inventory could potentially be flooded into the system and the market might not be able to absorb all of it, resulting in increased pricing pressure,” Citi said in an early May note.

Source: mining.com

Study yields new insight in hunt for rare, valuable yellow diamonds

Yellow diamonds, some with colourless cores

A new study by University of Alberta scientists could help guide the search for rare, high-value yellow diamonds in the Canadian North.

The researchers, led by PhD student Mei Yan Lai, examined the chemical makeup of stones recovered from the Chidliak and Ekati mines in Northern Canada to get a better understanding of how they formed.

“Without this research, we wouldn’t know that two separate formation events occurred, and that the second, more recent event is responsible for the yellow colour,” explained U of A diamond geologist Thomas Stachel.

“The more we know about the origin of these potentially high-value diamonds, the better results for diamond exploration and value creation in Northern Canada.”

Lai said they wanted to understand the origin of the yellow colour in the diamonds from the two deposits.

“Canadian yellow diamonds have never been studied spectroscopically in detail. Our results suggest that the cause is the preservation of unstable single nitrogen atoms preserved inside the diamonds,” explained Lai, who conducted this research as part of her master’s studies in the Diamond Exploration Research Training School under the supervision of Stachel.

The research team determined that some yellow diamonds contain colourless cores, meaning that the yellow outer layers crystallized on top of clearer centres. Lai determined that the yellow diamonds crystallized no more than 30,000 years before the kimberlite eruptions that brought them up to Earth’s surface.

“Our analysis shows that the colourless cores in these yellow diamonds are about one billion years older,” Lai said. “In fact, the carbon isotope compositions and nitrogen concentrations of the colourless cores and yellow outer layers are significantly different, suggesting that they formed in at least two distinct events and involved different diamond-forming fluids.”

The researchers said discovering a potential new source of yellow diamonds in the Canadian North is economically significant, as the previous main source of high-quality yellow diamonds, the Ellendale Mine in Western Australia, was recently shut down.

The discovery of colourless cores in some of the yellow diamonds may also be of interest to the jewelry trade, said Lai.

“Occasionally, rough yellow diamonds lose their vibrant yellow colour after being cut and polished—probably because this kind of diamond has a thin layer of yellow overgrowth on top of the geologically older colourless core,” she said.

The project is a collaboration with Dominion Diamond Mines and Peregrine Diamonds Ltd. Part of the analyses were done at the Gemological Institute of America.

The research is supported by a bursary through DERTS, funded by the Natural Sciences and Engineering Research Council of Canada’s Collaborative Research and Training Experience program.

The study, “Yellow Diamonds With Colourless Cores—Evidence for Episodic Diamond Growth Beneath Chidliak and the Ekati Mine, Canada,” was published in Mineralogy and Petrology.

Source: miragenews

Israel Gives $284M Boost to Diamond Trade

The Israeli government has pledged $284 million (NIS 1 billion) to guarantee bank loans to diamond companies in an effort to ease the trade’s severe credit difficulties.

A lack of credit is stifling growth, especially among the smaller firms that constitute about 70% of the Israeli trade, according to a special committee set up to investigate the sector’s challenges.

The team — led by Naama Kaufman-Pass, deputy director-general of the nation’s Ministry of Economy and Industry — released its findings earlier this month, highlighting several ways in which the industry had hit a crisis.

Banks’ perception of the diamond sector as high-risk has led to a decline in total lending to the Israeli trade from $2.5 billion in 2008 to about $1 billion last year, the committee said in its report. Financial institutions are also refusing to accept dealers’ inventory as collateral, while competition from India and Belgium has added further damage to Israel’s market position.

To this end, the government fund will back companies’ borrowing, meaning that if they fail to repay a loan to a bank, the state will pay. While the committee submitted the policy to Eli Cohen, minister of industry and economy, as a recommendation, the lawmaker said the government was set to go ahead with the program.

“We have decided to allocate another billion shekels over the next five years to the diamond sector through credit guarantees,” Cohen told an audience at the International Diamond Week in Israel last week.

In addition, the committee suggested the government provide money for the bourse’s newly launched innovation laboratory, put cash into bringing more diamond buyers to Israel, support efforts to develop e-commerce opportunities, and contribute to other projects to boost the industry.

“The committee identified the main hurdles in small businesses’ activities in the sector, and its recommendations offer a comprehensive response to its needs,” Kaufman-Pass said.

The diamond trade is an important segment of the Israeli economy, representing about 13% of total exports, and employing about 9,500 people, according to the report. However, the 2008 global financial crash led to a 27% slump in Israel’s polished-diamond exports between that year and 2016, with the Chinese market slump in 2015 also denting demand.

“Implementing the committee’s conclusions, alongside other steps, is essential, considering the crisis the sector has been through,” Cohen added in a statement. “Their purpose is to provide new tools to help deal with challenges in the trade and to ease regulation, thereby growing both production and exports.”

Shay Rinsky, director-general of the Ministry of Economy and Industry, set up the committee in September to delve into issues of credit and growth in the diamond trade and examine how to bring the industry forward.

Source: diamonds.net

Diamond Miner Gem Diamonds Finding More Huge Stones

Gem Diamonds has recovered another 100 carat plus rough diamond this year.

The recovery of the D colour type IIa stone shortly after the recovery of a 910 carat D colour IIa rough diamond from Letšeng last week.

Gem Diamonds began extracting ore from a higher grade part of Letšeng last year, resulting in the increase of large stones.

Gem Diamonds Letseng mine is located in the mountainous kingdom of Lesotho in southern Africa.

Two 100 carat plus rough diamonds recovered at Lesotho mine

Gem Diamonds Lesotho mine in southern Africa

The two Rough diamonds each weighing more than 100 carats were recovered by Gem Diamonds at the Lesotho mine in southern Africa.

Both rough Diamonds weight 117 carats and 110 carats are D color Type IIa diamonds.

Type IIa diamonds carbon bonds contain little or no nitrogen atoms making them very white and rare. These are the most expensive white diamonds.

$16.5 Million for 476 Carat Meya Prosperity Diamond

Graff Jewellers a leader in the diamond business since 1960 has purchased the 476 carat rough diamond named The Meya Prosperity Diamond.

The Rough diamond was mined in Sierra Leone.

Graff paid $16.5 million for the exceptional rough diamond , another in a long line of extraordinary diamond bought by Graff.

The magnificent rough diamond is the 29th largest diamond ever recovered and is the fifth largest stone from Sierra Leone.

Yellow Diamonds Sell At Bonhams

In 1940 when R.V. Cullinan the son of the renowned diamond magnate Sir Thomas Cullinan asked De Beers director Pierre De Villiers to buy him some diamonds on his next visit to Kimberley.

A collection of Fancy Vivid Yellow Diamonds owned by South Africa’s mining elite has sold at a Bonhams auction for well above its expected price.

The collection sold as two separate lots at the for a total of $773,350.

Graff Blue Diamond Ring Fetches $12.5 Million

A crossover ring with two fancy vivid blue diamonds designed by Graff Jewellers has smashed its pre-sale estimate.

The ring has sold at the Christie’s New York Magnificent Jewels auction fetching more than $12.5 million USD.

$33.8 Million For The 163 Carat Flawless Diamond At Geneva Auction

163ct De Grisogono Emerald Shape Diamond

The largest diamond offered at an auction went under the hammer in Geneva Tuesday setting a world record for a diamond of its shape.

The D colour 11A type flawless diamond was Polished from a 404 carat rough diamond which was recovered in February 2016 in the Lulo mine in Angola.

The 163.41 carat called The Art of Grisogono, sold for $33.8 million, after taxes and commissions, at the Christie’s autumn jewellery auction.