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christies green diamond
A 6.13-carat fancy intense green diamond set a new per-carat record when it sold at Christie’s on May 27 for a whopping $3.6 million, or $594,510 per carat. The square cushion cut diamond is the center of a rose gold halo style ring, accentuated by natural pink diamonds.
Next to red, green is the rarest of colors found in natural diamonds. For most colored diamonds, the color comes from trace amounts of mineral impurities or extreme pressure conditions while the diamond was forming. The tight chemical structure makes it very difficult for any impurities to enter, which is why colored diamonds are exceedingly rare. Small amounts of boron in the crystal lattice structure of a diamond, for example, will impart a blue hue; same goes with nitrogen for yellow, and hydrogen for violet. What gives a diamond a green hue however, is the presence of natural radiation over millions of years. Because the radiation exposure is an external force rather than internal force (such as mineral impurities and lattice defects), it acts on the surface only. As a result, green diamonds are not green all the way through; the color is concentrated on the outer layers and tends to be weakly saturated. That is why a fancy intense green diamond, especially one of a size like this one, is almost a once-in-a-lifetime find.
This spectacular diamond joins the ranks of other recently sold, record-breaking gems at Christie’s. At their Geneva auction just last month, there were three record-breakers alone. They include ‘The Blue’, a fancy vivid blue pear shaped diamond weighing over 13 carats, a 76.5 carat light pink square-cut diamond that sold for $10.2 million, and the ‘Ocean Dream’ – a 5.5 carat, vivid blue-green diamond that went for $8.8million.
Tags: Christie's Geneva, engagement ring, fancy deep, fancy intense, fancy light, fancy vivid, green diamond, Hong Kong, jewelry auction, natural diamonds, Ocean Dream, pink diamonds, rare, rose gold, The Blue, vancouver
With its range in color from sunny yellow to bronze deep orange hues, what better stone to represent the falling leaves of autumn than citrine? One of the official birthstones of November, citrine is a member of the mineral family quartz.
Currently the world’s largest faceted citrine resides in the “Special Exhibit Gems” of the Art Natura museum in Spain, a natural science museum that is home to an extensive collection of colored gemstones. Known as “The Malaga” in tribute of its host city, this oval shaped gem is an enormous 20,200 carats – equivalent to 4 kilos! It neighbors another gemstone of gigantic proportions: the “Eldorado”, a 31,000 carat imperial topaz which also happens to be the other birthstone of November.
Despite its size, “Malaga” has very minor imperfections and is considered nearly flawless. Along with its exceptional color, even distribution, transparency and purity, “Malaga” is truly a world-class gem. Citrine crystals that are found usually measure only a few cm across, and the ones that are larger in size generally lack in quality and are used for decorative purposes rather than jewelry.
The rough that formed “Malaga” was originally discovered in 1990 in Brazil. Due to the complications of the process of cutting and polishing a stone this large, the rough was left untouched for nearly two decades until 2009 when a team of gem cutters took on the challenge. With all of the special considerations needed for a stone of this size, it took over a year to bring to its polished form.
Brazil is the largest producer of the world’s supply of citrines; other important sources include Bolivia, United States, and Madagascar.
Tags: amethyst, Brazil, citrine, largest gemstones, Malaga, mineral family, museum of natural history, quartz, tourist sites
The New York Museum of Natural History is having an exhibition for the rare 19th century 55 carat diamond that was once part of the Russian Crown Jewels.
The stone is named “Kimberley Diamond” after the Kimberley Mine where it was discovered in South Africa in 1868. It had been cut from a 490 carat crystal. In 1921 it turned into a 70 carat gem and later in 1958 was re-cut and improved for brilliance and proportions. In the re-cutting process the stone lost some weight 14.92 carats. Now weighing 55.09 carats it was valued at $500,000 but is probably worth considerably more now.
Kimberly Diamond has been perfected to a champagne coloured, emerald cut, rectangular flawless diamond. It is about 1.25 inches in length. It has been described as a “cape diamond” which is an Old World term meaning “deep colour.”
In order a diamond to survive the Earth’s surface it has to get there really fast this stone got a ride on magma. Magma starts very deep in the earth and moves towards the surface at 35-40 km/h. During a volcanic eruption the magma creates bubbles like champagne and can reach speeds up to Mach 2 (twice the speed of sound).
Diamonds were first found along rivers where people would look for gold. In the 1870’s lots of diamonds were found at the bottom of rivers and streams in South Africa. They would follow the river upstream and find a grey blue rock which contained a diamond. Now days a gem the size of the Kimberley diamond wouldn’t survive in modern mining techniques it would be crushed in the process.
The diamond will be on display with “Patricia Emerald” and “The Star of India.” Patricia Emerald is a 632 carat 12 sided emerald crystal from Columbia. The Star of India is the world’s largest gem quality blue star sapphire it is 526 carats in weight and is 2 billion years old!
Kimberly Diamond is on loan from Bruce T. Stuart. The stones will be added to the Morgan Memorial hall of Gems and is on display in the NYC museum through to June 2014.
Tags: 55 carat, blue star, carat, champange colour, diamond, emerald cut, flawless diamond, gem, gem quality, gold, kimberley, kimberly diamond, kimberly mine, mach 2, mining, museum of natural history, new york museum, new york museum of natural history, nyc museum, proportions, rare stone, russian crown jewels, sapphire, south africa mine, star of india
The most flawless, biggest briolette ever to surface at auction weighing at a stunning 75.36ct broke records! This diamond was sold for a world record at $11,145,734 from an anonymous buyer at Christie’s Hong Kong’s Magnificent Jewels sale. This pendant necklace was originally valued at a pre-sale low estimate of $8.5 million, which it easily surpassed. It did fall short of its high pre-sale estimate of $12.5 million.
The briolette is a traditional cut popular in the Victorian times but has recently become more popular in precious and semi-precious stones. It is a stone cut into a three-dimensional waterdrop shape. Its elegant pear shape with cut facets dangles below a marquise-cut purplish-pink diamond. Adorned with stations of smaller briolettes with 18 karat white and rose gold adjustable neck chain, this piece is a classy stunner!
An auction spokesperson said the diamond was “perfect,” and had the proof of an assessment with the Gemological Institute of America. The GIA rated the stone Type IIa, which is the top quality grade. The diamond is similar to the British Queen Elizabeth’s one she has set in her crown. Christie’s jewellery specialist, Chiang Shui-Fung, says the diamond is extremely rare.
The briolette is special because they have to find a piece rough and big enough to cut into that style. The diamond came to an American dealership named William Goldberg, as a 160.5- carat rough weight and had to be shaped into the now 75.51 carat diamond. To achieve this brilliant rare cut William Goldberg had to sacrifice more than half the stone’s weight in the meticulous cutting process. The diamond is now a stunning piece and will be remembered as a historical record breaking event.
Tags: 18 karat, briolette, briolettes, carat diamond, christie, crown, flawless, gemological institute of america, goldberg, jewel, magnificent jewels, marquise, million, necklace, pear shape, perfect, quality grade, sale, size, stone, stunner, Type IIa, victorian, victorian times, waterdrop, world record
The Australian Argyle Diamond Mine will feature three ultra-rare red diamonds in the upcoming Pink Diamond Tender. This is the most it has featured in 30 years. They began mining in 1983 and only six diamonds have come out of the mine as certified Fancy Red by the Gemological Institute of America. This is a very notable time for red diamonds.
Also for the first time in eight years it will feature a diamond bigger than 3 cts: a 3.02 ct. fancy pink radiant going by the name of “Argyle Imperial.” There is another weighing at 1.56-carat which is round fancy red called the “Argyle Phoenix.”
Josephine Johnson Argyle Pink Diamonds Manager had this to say about it. “Since mining began in 1983 only six diamonds certified as fancy red by the Gemological Institute of America have been presented for sale at the annual tender. To have three of these rare red diamonds in one tender is a very special moment in time.” They will be presented for sale at the annual tender. The diamonds will have their world debut first in Sydney. Then tender viewing will take place in Hong Kong, Perth, and previews in Tokyo and New York with bidding closing in October. All vividly naturally coloured diamonds are expensive but red diamonds are so rare that many think their price might double in the next couple of years.
The Argyle mine produces the world’s entire supply of pink diamonds with the red seen as the top pinnacle of the colour scale. Japan is the largest consumer of pink diamonds since the cherry blossom tree inhabits the land there the shade of pink is highly favorable to them.
Fancy red diamonds are the rarest naturally coloured diamonds. Very few diamonds receive a grade of fancy red. This grade of fancy red means that the diamond is pure red and has no modifying colour. No one really knows how the diamond gets to be this colour. It is thought that it gets its colour from a molecular structure distortion as the jewel journeys up from the crusts earth to the surface. Another thought is that the diamond could get its colour from nitrogen atoms. Diamonds are made up of carbon atoms bonded together, sometimes there are gaps within these atoms and scientists think that the gaps and nitrogen cause the red colour. They are shaped by millions of years of crystallization. Either way the natural colour of a fancy red is unmistakable and breath taking. Diamonds come in different colours including, champagne, yellow, pink, red and purple. Natural and treated colour diamonds are two completely different markets.
Check out a local jewellery boutique store for more information and to view some different coloured diamonds in a variety of shape and cut. If you are looking for that perfect custom diamond to add to an engagement ring its best to shop at a local jewellery store where they have trusted customer service and can help you find the exact unique coloured stone that’s right for you.
Tags: argyle diamond, argyle mine, carat, colour scale, coloured diamonds, diamond mine, gemological institute of america, jewel, pink diamond, pink diamonds