From rubies and emeralds to rare coloured diamonds
Specialist David Warren provides an in-depth expert guide for buyers seeking a bright addition to their collection
1) Fancy or Vivid? Get to know your terminology
A highlight in the coloured stones category — often setting world-record prices — coloured diamonds come with their own specific colour categories. A blue diamond, for example, could be classified as Faint Blue, Very Light Blue, Fancy Light Blue, Fancy Blue, Fancy Intense Blue, Fancy Dark Blue, Fancy Deep Blue or Fancy Vivid Blue. The same principle of categorisation applies to coloured diamonds of virtually all hues.
2) Word order is important
Coloured diamonds aren’t always a single colour. You may sometimes see a diamond described as ‘Vivid Orange Yellow’ — or even ‘Vivid Yellow Orange’. But what’s the difference? The key here is to look at the last word, which will be the principal colour. A pair of Vivid Orange Yellow diamond earrings were recently sold by Christie’s in Geneva, for example, where the colour was considered marginally more towards yellow than orange.
You can also have an ‘Orangey Yellow’. Here, yellow remains the dominant colour, with just a touch of orange; it’s not as orange as an ‘Orange Yellow’.
3) Are some colours more valuable than others?
The rarest of the rare is a red diamond — there aren’t many, and they’re generally not very big. It would be exceptionally unusual to find a red diamond above 2 carats.
4) How are coloured diamonds graded?
Christie’s sends diamonds to the GIA laboratory (the Gemological Institute of America), which provides the world’s most trusted colour grading service. It’s often worth doing, even if you have a stone with a weak colour — particularly if the colour is faint pink, green or blue, for example, which could still be significantly valuable.
A weak yellow diamond, however, might not be, as it is not uncommon to find stones with a yellow tinge. Other colours that may still be attractive and collectable but far less expensive include brown, yellowish brown, greenish yellowish brown, brownish yellow, yellowish brownish green. There are many colour combinations — even black.
5) Where do coloured diamonds come from?
Mining coloured diamonds is really a matter of chance. The only exception is the Argyle mine in Australia, owned by Rio Tinto, which is the only mine in the world to consistently produce pink diamonds, and is also the world’s largest supplier of natural coloured diamonds.
Diamonds in their purest form are white — as are all other gemstones, except three: opal, turquoise and peridot. What turns them a particular colour is the presence of an accidental colouring agent. A blue diamond, for example, will contain a tiny amount of boron in the composition of the stone. Green diamonds acquire their colour from radiation in the ground, while yellow diamonds are created when nitrogen enter their chemical composition. Pink diamonds result from a ‘slip’ in the stone’s lattice structure.
6 What about other coloured stones? Is there such a thing as a perfect emerald?
When it comes to emeralds, the most coveted are a darkish green. It’s important the stone isn’t too dark, however: the highest-quality emeralds combine good colour with clarity. Imagine if you were to take an empty wine bottle made from green glass and hold it up to sunlight — that’s a good indication of the perfect shade.
The proportions of an emerald (or any gemstone) are also important. If they’re poor, light will diffract and go through the stone, rather than bouncing around within it, coming out, and hitting the eye — a phenomenon known as total internal refraction. While fissures, known as ‘inclusions’, are common, too many will affect the beauty of the stone and lower its value.
Although highly rare, it is theoretically possible to get an emerald so perfect in terms of colour, clarity and brightness that it comes close to resembling the brilliance and ‘fire’ of a diamond (I have only ever seen a handful of emeralds that fall into this rare category).
7) What about rubies and sapphires?
The same concerns apply — as with emeralds, buyers of rubies and sapphires should look for stones with an appealing colour, good clarity, and attractive proportions.
A small percentage of the top rubies have a colour referred to as ‘pigeon’s blood’ — a dark red — though must not be too dark. Aim for a rich, warm burgundy that makes you joyful when you look at it.
8) Is origin relevant?
For coloured gemstones, this is a point to be considered, with the top emeralds mined in Colombia, the finest rubies coming from Burma and, for sapphires, the cream of the crop hail from Kashmir. However, it is important to remember that attractive gemstones do come from many different localities, and it is all about the beauty of the colour and the budget available.
9) How important is carat?
It’s a common misconception to think that stones with a higher carat weight are always more valuable. They often are, but you could have a 50-carat emerald that’s worth say $500 per carat — or a five-carat emerald worth $30,000 per carat. The same is true for all stones. It’s a combination of the ‘four c’s’: colour, clarity, cut and carat weight.
10) Should I be wary of treated stones?
Man has a long history of tampering with coloured stones. Emeralds, for example, often have fissures that break the surface, which can be filled with oil or plastic resin. The oil or resin is designed to have the same refractive index as the stone and, once absorbed into the fissures, the inclusions become less apparent. This practice is one that goes back 4,000 years to Ancient Egypt, when natural oils were used.
The degree to which an emerald has been improved with an enhancement agent is graded from none to insignificant, minor, moderate or significant. Oil, though considered to be gentler, can have the disadvantage of leaking from the stone over time, unlike resin, which is permanent. There’s nothing wrong with buying an enhanced stone, as long as the degree of enhancement is reflected in the price — though a beautiful untreated emerald will be worth far more than a beautiful treated emerald.
11 What about coloured diamonds?
Buyers should ensure that the diamond’s colour is natural. Concerning green diamonds, it’s important to verify that the radiation that gave the stone its colour occurred in the ground, and not in a laboratory — one of the hardest tests for the GIA to determine.
Blue diamonds can also be created through artificial irradiation, but mostly look obviously wrong. Similarly, the colour of yellow stones can be enhanced, with the most famous example of an enhanced stone being the Deepdene Diamond, weighing 104.52 carats.
12 How should I care for coloured stones?
One golden rule is: never carry gemstones in a pouch. Sadly, it’s something I’ve seen too often, and results in badly damaged stones. The resistance of minerals is assessed using ‘Mohs scale of hardness’. If stored with other stones, a diamond will scratch another diamond, and any stone softer than it. Sapphires will scratch everything that is softer than them, and so on, down the scale.
It’s a mistake, however, to think that diamonds are indestructible. Although they are the hardest substance known to man, they do have a certain brittleness. A diamond can chip, for example, if it hits a hard surface like marble. Here, weight becomes critical: if a diamond is damaged, it can be re-cut to remove any chips, but in doing this there will be a loss of weight. If a stone weighing 10.05 carats drops to 9.95 carats, the impact on value can be significant, because it has dipped below 10.00 carats. A loss of half a carat in a 15.75 carat stone, on the other hand, may do little to alter value.
58 posts categorized "Colored Diamonds"
The oval-shaped 59.6 carat stone was bought after just five minutes' bidding at Sotheby's, reports said.
It is the largest polished diamond in its class to go under the hammer.
It sold for $83m in Geneva in 2013 but the buyer later defaulted. The record until now was held by the Oppenheimer Blue, which sold for $50m last May.
Bidding for the gem, which was found by De Beers at a mine in Africa in 1999 and cut over a period of two years, began at $56m.
Sotheby's said the buyer was Hong Kong jewellery retailer Chow Tai Fook Jewellery.
Alexander Breckner, head of diamonds at jewellers "77 Diamonds", told the BBC that the stone was exceptional.
"It's the largest pink diamond ever found in the history of humankind. It's an incredible colour to it.
"And the sheer size of the stone already makes it so rare and so beautiful."
New York--Two large diamonds have been uncovered in Africa in as many weeks, putting an end to the drought of big diamond finds the industry seems to have been experiencing.
Gem Diamonds uncovered the 114-carat D color, Type II rough diamond on the left at Letšeng while Firestone Diamonds found the 110-carat light yellow rough diamond at right at its Liqhobong project.
Mining company Gem Diamonds Ltd. announced the recovery of a 114-carat rough diamond from its Letšeng mine in Lesotho on Friday.
The company described it as a D color, Type II diamond of “exceptional quality.”
The Letšeng mine is known for producing large, high-quality white diamonds, selling at an average price of $2,000 per carat, according to Bloomberg, which is the highest in the industry.
It is the deposit responsible for producing the 357-carat chunk of rough that was cut into the 118.78-carat “Graff Venus,” the world’s largest flawless heart-shaped diamond.
Since Gem Diamonds acquired Letšeng in 2006, the mine has produced four of the 20 largest gem-quality white diamonds ever recorded, though last year it only recovered five stones bigger than 100 carats, less than half what it found the year prior.
The news of Gem’s find came on the heels of another big diamond find from a rival miner in Lesotho, a small kingdom within a country that’s located in the southeastern portion of South Africa.
On April 5, Firestone Diamonds said it had unearthed a 110-carat diamond, its biggest discovery so far, at its new mine in Lesotho.
The light yellow stone was discovered at the Liqhobong project, confirming its beliefs that the deposit has the potential for large diamonds, the company said.
Firestone has spent $185 million to build up the mine, which just began production in October.
In addition to its Liqhobong mine in Lesotho, Firestone also owns and operates the BK11 kimberlite mine in northern Botswana.
Hong Kong--The 59.60-carat ‘Pink Star’ diamond has, once again, become the most expensive jewel ever sold at auction, and maybe this time it will stick.
The Pink Star is a 59.60-carat oval mixed-cut Type IIa pink diamond and is the largest internally flawless fancy vivid pink diamond the Gemological Institute of America has ever graded. The diamond came from a 132.5-carat piece of rough mined by De Beers in Africa in 1999 and was cut and polished over a two-year period.
Chow Tai Fook paid $71.2 million for the stone on Tuesday at Sotheby’s Magnificent Jewels and Jadeite sale in Hong Kong. The Hong Kong-based retailer and manufacturer edged out two other buyers to snag the stone, Sotheby’s said.
Sotheby’s experts had estimated before the sale that The Pink Star would sell for more than $60 million.
It set a new world record price for any jewel sold at auction, surpassing the rectangular-cut, 14.62-carat “Oppenheimer Blue,” which sold for $57.5 million at Christie’s Geneva last May.
This isn’t the first time The Pink Star has found a buyer at auction, though the first sale fell through.
The nearly 60-carat pink stone went up for auction in November 2013 at Sotheby’s Geneva, where four different bidders competed for it. New York diamond cutter Isaac Wolf placed the winning bid of $83 million, which, at the time, marked a new auction record for any jewel ever sold at auction.
In February 2014, though, Wolf defaulted on the payment for the diamond he had named “The Pink Dream” and as a result, Sotheby’s had to take the stone back into its inventory because it had been sold under an auction guarantee.
Last summer, the auction house formed a partnership with Diacore and Mellen Inc. to acquire an ownership interest in the diamond, meaning that when the stone sold, proceeds would be split among the three companies per their ownership percentage.
The 2016 JCK Jewelers’ Choice Awards: The Winners
You’ve got to hand it to JCK’s readers: They know a good ring when they see it.
For the third straight year, that style has nabbed top honors in our retailer-voted Jewelers’ Choice Awards. In 2014, it was a sweet morganite cocktail ring by Yael Designs. In 2015, a luminous Lightning Ridge opal ring from Omi Privé. And this year, the grand-prize winner is Rahaminov Diamonds’ dazzling Rosé ring.
Varied as they are, each of those rings has had one thing in common: an indisputably stunning center stone. “The diamond dictates the design,” says Rahaminov owner-designer Tamara Rahaminov Goldfiner. In this case, it’s a 2.32 ct. natural fancy pink VVS1 GIA oval diamond, which went on the wheel “several times,” she explains, “to maximize its beauty, shape, color, and clarity.” Trust us when we tell you the gem generated enough sparkle to stop traffic. (Don’t worry, Tamara—we didn’t actually take it outside into traffic.)
Of course, there’s plenty of sparkle coming from all of our honorees—47 winners in 20 categories (including one timely addition for 2016: Lab-Grown Diamond and/or Gemstone Jewelry). Which should be more than enough to throw yourself one blinding ring party.
De Beers Millennium Jewel Sells for $32 MillionThe 10.1 ct. internally flawless fancy vivid blue was nearly stolen in a famed failed heist
The oval-shape 10.1 ct. internally flawless fancy vivid blue diamond’s price came out to $3.1 million per ct. The final price, while still substantial, was toward the lower end of its $30 million–$35 million estimate.
It is just one of a number of blue diamonds to hit the auction block recently:
- In November 2015, the 12.03 ct. internally flawless fancy vivid Blue Moon sold for $48.5 million, a world record for any diamond.
- The Shirley Temple Blue, a 9.54 ct. fancy deep blue worn by the actress, will be auctioned at the Sotheby’s Magnificent Jewels sale on April 19 in New York.
- On May 18, Christie’s will auction the 14.62 ct. fancy vivid Oppenheimer Blue. Its estimate is $38 million– $45 million.
The De Beers Millennum Jewel 4 is known for nearly being snatched while on display in London’s Millennium Dome in a famed failed heist. On Nov. 7, 2000, a gang of theives drove a bulldozer past a security guard, donned gas masks, and set off smoke bombs, intending to bash through the display cases with hammers, snatch the jewels, and escape on speedboats waiting on the nearby Thames River. It would have been the largest jewel heist in history.
According to histories of the event, the gang was already under surveillance by police because of two attempted heists. Thanks to a tip, police noted gang members repeatedly visiting the Dome during high tide on the Thames. From that point forward, police flooded the Dome with policemen on days of high tide. The day of the robbery, the Dome replaced the jewels with fakes and police were waiting. The men ended up trapped in the Dome vault and were easily overpowered without any shots being fired.
The diamond was also renamed 'Blue Moon Of Josephine'. This comes just a day after the tycoon, affectionately known as Big Liu, spent a whopping $40.4 million (Nearly Rs 268 crores) over a 16.08 carat pink diamond for his daughter that he also renamed 'Sweet Josephine'.
Six years back, he bought then 1-year-old Josephine her first major diamond; a 7.03-carat blue diamond for US$9.48 million (Nearly Rs 63 crores). This diamond was renamed by him as the 'Star of Josephine'.
While you marvel at the luck that follows the young josephine, let us tell you that she is not the only lucky daughter of Joseph. Her elder half-sister, 14-year-old Zoe also got two amazing gifts last year. She was gifted with a 9.75-carat 'Zoe Diamond'(US$32.6 million), and a 'Zoe Red' ruby (S$11.9 million).
Big Liu surely knows his way into his daughters' hearts and he knows the one universal truth that"Diamonds are a girl's best friend".
The 12.03-carat diamond, named the “Blue Moon” because of its rarity, will lead Sotheby’s Magnificent Jewels and Noble Jewels sale scheduled to take place Nov. 11 in Geneva.
The cushion-shaped, brilliant-cut stone boasts an exceptional clarity, declared internally flawless by the Gemological Institute of America.
It comes to market with an estimate of between $35 million and $55 million. If it sells at the high end of that range, the stone could become the most expensive diamond in auction history.
The current record is held by the Graff Pink, a 24.78-carat fancy intense that went for $46.2 million at Sotheby’s Geneva in November 2010. (Sotheby’s actually topped the Graff Pink sale in November 2013 when it sold the 59.6-carat “Pink Star” for $83.2 million, but the record didn’t hold as the buyer couldn’t pay for it, requiring Sotheby’s to acquire the stone itself.)
Scientists from the National Gem and Mineral Collection at the Smithsonian Institution were able to study the Blue Moon diamond, noting that the color of the blue diamond is “true and saturated” throughout, with no other colors present.
The polished stone was cut from a 29.62-carat piece of rough unearthed at Petra Diamonds’ Cullinan mine in South Africa in January. A month later, Cora International NY purchased it for $25.6 million, or $862,780 per carat.
Sotheby’s also currently holds the world auction record for a blue diamond. This was set by the Zoe diamond, a 9.75-carat fancy vivid blue diamond that sold for $32.6 million in November 2014 during its sale of the late “Bunny” Mellon’s jewelry.
“Weighing in at 12.03 carats, the Blue Moon diamond is a simply sensational stone of perfect color and purity, combined with a superb cushion shape,” said David Bennett, worldwide chairman of Sotheby’s International Jewellery Division. “Blue, for me, is the most mysterious and magical of all the colors of diamond, and the Blue Moon will now take its place among the most famous gems in the world.”
Rio Tinto once again has four fancy reds in its annual tender of special stones from the Argyle in Western Australia, the mine that produces the vast majority of the world’s pink and red diamonds.
Including the four fancy reds, there are total of 65 diamonds in this year’s Argyle Pink Diamonds Tender, up from 55 last year.
There also are five “hero” stones this year, top-quality diamonds to which Rio Tinto assigns a name.
This year, Rio Tinto’s partnership with The Australian Ballet inspired the names assigned to the hero stones.
-- Argyle Prima, a 1.20-carat pear-shaped fancy red
Viewings of the Argyle Pink Diamonds Tender in Hong Kong are by invitation only. Following the viewings there, Rio Tinto will bring the diamonds to New York and then back to Australia.
Tender bids are scheduled to close Oct. 21.
The auction market got a shot of adrenaline last night, as the Sotheby’s Geneva sale set a world record for any jewelry auction—and capped that with six more world records, almost all for colored stones.
The auction fetched $160.9 million, or 149.9 CHF (Swiss francs). That tops the previous record holder, the Christie’s November auction in Geneva, which fetched 147.2 million CHF. (Sotheby’s briefly claimed the title for its $199 million November 2013 sale, but that didn’t stand after an $83.1 million pink diamond sale was canceled.)
The sale gives a nice boost to the Sotheby’s jewelry sales, which were down two percent in the first quarter of 2014, according to its 10-Q.
The 25.59 ct. Burmese Sunrise Ruby sold for $30.3 million ($1.1 million a carat), doubling the low end of its $12 million to $18 million estimate. The stone set records for a ruby, both in total price and per-carat price; for any non-diamond jewel; and any stone by Cartier. The buyer was not named.
The blood-red stone was a favorite of Sotheby’s worldwide jewelry chairman David Bennett, who said last month: “I have remained in awe of the Sunrise Ruby since the first moment I set eyes on it. In over 40 years, I cannot recall ever having seen another Burmese ruby of this exceptional size possessing such outstanding color.”
The Sunrise sale significantly tops the ruby record set just six months ago by the 8.62 ct. Graff Ruby, which sold for $8.6 million at Christie’s Geneva in November 2014.
The Historic Pink Diamond, an 8.72 ct. fancy vivid pink, achieved $15.9 million, which fell within its $14 million to $18 million estimate, and also went to an unnamed buyer. The diamond is believed by the Gemological Institute of America to have been part of the outstanding collection of Princess Mathilde of Bonaparte, Napoleon I’s niece. It only recently resurfaced, having been kept in a bank vault since the 1940s.
The other records were set for sapphires and pearls:
- A pair of very fine Burmese sapphire and diamond ear clips with a combined weight of 32.67 cts. sold for $3.2 million, setting a world record price for a pair of Burmese sapphire earrings.
- A Kashmir sapphire and diamond brooch weighing 30.23 cts. sold for $6.1 million, setting a record for a Kashmir sapphire (the previous record was set in November).
- A rare natural pearl and diamond necklace sold for $7 million, setting a record for a two-row natural pearl necklace.