Sunday, May 18, 2014

Rare and Important Colored Diamonds


When one hears the word "diamond," images of bright sparkling white stones enter the mind like those seen just below. Most of these "white" diamonds we see are found in what is called the "normal" color range. These are colorless to very light yellows and browns that fall in a range of saturation written in letters as D-Z on the GIA (Gemological Institute of America) color scale. Beyond this color range if there is a higher saturation of yellow or brown, or any color other than these two, the diamond is referred to as "fancy."

near colorless diamonds

Except for yellows and browns, most naturally occurring colored diamonds are fairly rare. For the most part, they get their hues from impurities and defects within the carbon crystal structure. There are also treatments one can apply to change the color or enhance it.

Here we will explore some of the greatest examples of naturally occurring colored gems that have been the allure of many generations.


Brown Diamonds:

The most commonly seen fancy color is brown. The color is caused by internal parallel grain lines within the diamonds structure.

In 1986 a 755.5 carat fancy yellow brown diamond rough was discovered in DeBeers' Premiere mine in South Africa. In order to cut the diamond, a special underground room was built that was free of vibrations. After two years of careful cutting, the diamond would ultimately surpass the Cullinan I (530.2 cts) at a final weight of 545.67 carats and steal the title of Worlds Largest Faceted Diamond.

The diamond was purchased from DeBeers in 1995 and presented five years later to the King Bhumibol Adulyadej of Thailand to mark his 50th anniversary as Monarch, his "Golden Jubilee," giving the diamond its name. The diamond was blessed by Pope John Paul II, the Supreme Buddhist Patriarch, and by Thailand’s Supreme Imam. It is currently housed in Bangkok as part of the crown jewels.

The Golden Jubilee Diamond

In 1853 at a diamond mine in Brazil, a slave worker turned in a large rough stone to her master. In exchange for her honesty (as was the custom here), she was rewarded with her freedom and a salary.

The rough would then go on to exchange several hands before being faceted into a cushion shaped gem showing a faint pinkish brown color, losing over half its original weight. The Star of the South became the first Brazilian diamond to receive international praise after being on display in London and Paris in the 1860s. At 128.48 carats, it was graded VS2 and Fancy Light Pinkish Brown.

The Star of the South


Yellow Diamonds:

The second most common fancy color in diamonds is yellow. The faint yellow hues that can been seen in the "normal" range of diamond tones grow less valuable as they become darker and move down the color scale towards Z. Interestingly, once they pass the normal scale into a higher saturation of vivid fancy yellows, they become much more valuable and sought after. The yellow one sees is caused by the presence of nitrogen within the diamond structure.

One of the largest and most famous fancy yellow diamonds is the Allnatt Diamond, which has been graded by GIA as a Fancy Vivid Yellow, with VS2 clarity. The 101.29 carat cushion cut stone achieved the highest auction price for a single yellow diamond when it went on sale at Christie's, Geneva, in 1996 for an incredible sum of $3,043,496 USD.

The Allnatt Diamond

A 287.42 carat rough discovered in South Africa in 1877, purchased by famed New York Jeweler Charles Tiffany, would end up yielding a 128.5 carat brilliant cushion cut diamond, famously known as the Tiffany Yellow. It would take a year of careful consideration and study of the stone before his gemologist would begin the cutting process, resulting in one of the world's largest and finest fancy colored gems.


The Tiffany Yellow Diamond in "Bird on a Rock"

In 1961 Audrey Hepburn would famously wear the Tiffany Yellow around her neck in the "Ribbon Rosette" setting as she posed for publicity photographs for the iconic movie "Breakfast At Tiffany's."

The Ribbon Rosette featuring the Tiffany Yellow at left; Audrey Hepburn wearing the necklace, right


Pink and Red Diamonds:

Pink diamonds get their color from graining within the diamond crystal structure, similarly to how a diamond reflects a brown hue.

The Pink Star, previously known as the Steinmetz Pink, is a 59.60 carat stone (carefully cut from a 132.5 carat rough over a period of two years) graded by GIA as Fancy Vivid Pink and Internally Flawless. It is exceedingly rare for a stone of this size to have such a great clarity and color.


The Pink Star

Unearthed in the DeBeers mine in South Africa in 1999, the cut stone was unveiled to the public in Monaco in 2003. It would then go on to be a part of the Smithsonian's "The Splendor of Diamonds exhibit along with several other notable stones, including the DeBeers Millenium Star (203.04 cts), the Allnatt (101.29 cts), the Heart of Eternity (27.64 cts), and the Moussaif Red Diamond (5.11 cts), among others as seen below.

The Pink Star and the Allnat Diamond are shown flanking the Millenium Star

The Pink Star would go up for auction with Sotheby's, Geneva, in 2013. It fetched a remarkable $83.2 Million USD sold to a New York diamond cutter buying on behalf of his client, who would then rename it the Pink Dream. Unfortunately, the client defaulted on payment for the stone and the auction house was forced to essentially buy the stone for $60 Million USD from the original seller as they had guaranteed a minimum sale price.

The Moussaief Red Diamond, also known as The Red Shield due to its cut, weighs a mere 5.11 carats, a fraction of some of the other fantastic diamonds highlighted here. Where it gets its fame is from the extremely rare deep red color. The 13.9 carat rough was discovered by a Brazilian farmer in a river deposit in 1990. It is the largest known fancy red diamond ever graded by the GIA.

The Moussaieff Red Diamond

Green Diamonds:

Most green diamonds exhibit a pale green hue that is light greyish in tone, sometimes brown. The green hue in diamonds is caused when it is exposed to high levels of radiation, mostly when diamond deposits are located near radioactive rock.

Interestingly, some green diamonds called "chameleon diamonds" will ordinarily under regular lighting conditions exhibit a pale green-grey hue. When exposed to heat or left in the dark for at least 24 hours, these diamonds change to a bright yellow color, lasting as long as the heat is applied or after it returns to regular lighting conditions.

Chameleon Diamond in different lighting

The Dresden Green exhibits a natural and stable blueish green hue which is caused by exposure to radiation over a long period of time beneath the earth's surface. It is also the largest naturally green hued diamond known to be in existence weighing an astonishing 41 carats and said to be internally flawless. Many green diamonds owe their color to the radiated surface which creates a skin-like greenish coating, however the Dresden is a uniform green throughout the interior of the stone.

 
The Dresden Green as a single stone

Believed to have originated from the Kollur mine in India, the diamond made its way to Europe where it was purchased  in 1726 by Augustus II of Poland, also known as Augustus the Strong, King of Poland and Elector of Saxony. Augustus the Strong, named so for his bearish physique and his prolific production of offspring (all but one, illegitimate heirs), was a great appreciator of luxury and opulence. He was responsible for many of Dresden's great collections of fine art, objects d'art, and fine jewels, all of which vastly contributed to the establishment of the city as a renowned cultural center. Coincidentally, it is he who was also responsible for the European discovery and production of fine porcelain, known today as Meissen, after the town where the porcelain factory was built.

In 1768, the diamond was featured in a setting comprised of 413 diamonds for use as a hat ornament, the very setting in which it remains today. It is still housed in the Green Vault in the Dresden Castle.

The Dresden Green in its current setting

Blue Diamonds:

Blue color is caused by the inclusion of boron within the diamond, with the color getting deeper as the amount of boron increases. Incidentally, the presence of boron also makes a diamond a great conductor of electricity. Rarely, a diamond's greyish blue color is caused by the presence of hydrogen.

Perhaps the most famous diamond in the world today is a mystic blue diamond of moderate size which currently sits on display in the Smithsonian Natural History Museum in Washington DC, known today as the Hope Diamond. This 45.52 carat Fancy Dark Greyish-Blue gem is cut in an antique cushion shape encircled by 16 white diamonds and suspended from a diamond necklace in a setting designed by Cartier.

The Hope Diamond

Since its arrival into Europe in the 17th Century, the diamond has exchanged hands between several members of the nobility and monarchs including King Louis XV and Marie Antoinette. Over the years the diamond has been associated with death and misery for those who should possess it. These accounts, however, remain unconfirmed and inconsistent with historical records. Since acquiring the stone in 1958, the Smithsonian Museum has reported nothing but good news as the Hope attracts many visitors. If there was a curse, it appears to have gone dormant.

The Hope, while considered irreplaceable and therefore priceless, has been insured by the Smithsonian for $250 Million USD.

The Heart of Eternity is a 27.64 carat blue diamond from South Africa's Premier Diamond Mine. It was unveiled to the public in 2000 as part of DeBeers' Millennium Collection. The estimated value is currently around $16 Million USD.

The Heart of Eternity


Black Diamonds:

Quite the opposite of the well known and highly sought after colorless diamonds, black diamonds appear opaque and return only reflected light from the surface. For most of the era of diamond trading black diamonds have been used as industrial grit (their constitution makes them very difficult to cut) and only gained popularity for use in jewelry settings in the 1990s.

It is rumored that ancient Italians believed a touch of the black gem could help to repair the relationship between quarreling couples. However, Indians believed the black diamond was a symbol of bad luck.

Loose black diamonds


There is an interesting fabled dark history surrounding a large black diamond called The Black Orlov, also known as The Eye of Brahma, which weighs 67.50 carats. Once part of a much larger stone of 195 carats, the gem was featured as an eye in a statue of Brahma, the Hindu God of creation, located at a shrine in Pondicherry, India. Legend has it that when the eye was stolen by a monk the diamond became cursed and has since been linked to the apparent suicides of three subsequent owners, each of whom curiously flung themselves from a great height to their deaths shortly after acquiring the stone. One of the poor souls, a Russian princess by the name of Nadia Vygin-Orlov, is where the diamond gets its name.

In the 1950s the large stone was then cut into three separate gems in an attempt to break the curse and since has been considered freed of its demons after passing through the hands of several dealers, all of whom seemingly went unscathed.

The Orlov diamond is currently set in a brooch surrounded by 108 diamonds, and suspended on a necklace chain made of 124 diamonds.

The Black Orlov Diamond