Images courtesy of the article from mining.com via Sotheby's
Ever wonder why colored diamonds are so valuable?
Fancy colored diamonds are many times rarer and more valuable than colorless diamonds. Colored diamonds come in virtually every color. Most people do not realize that diamonds come in colors such as yellow, blue, pink, green, orange, purple, and red. They also come in combinations of these colors such as yellowish-green, grayish-blue, and orangy-pink. The levels of color saturation in colored diamonds is based on a GIA grading scale and the four most common levels in order of lowest color saturation to highest color saturation are Fancy Light, Fancy, Fancy Intense, Vivid. There are other less common levels such as fancy deep and fancy dark.
Yellow diamonds are the most popular of all fancy color diamonds. They are readily available in a variety of shapes and are often featured in designer jewelry collections. In the last few years, collections from retailers like Tiffany & Co. have popularized the hue, and large yellow diamonds have made headlines for prices garnered at auction. "The Vivid Yellow," a 32.77 carat fancy yellow diamond, fetched $6.6 million at Christie's in October 2011. A month later, the 110.03 carat "Sun Drop" sold for a record $12.3 million, the highest price paid for a yellow diamond at auction, until last Tuesday with the 100.09-carat “Graff Vivid Yellow” diamond, one of the world’s largest cut precious gems of any colour, fetched an astronomical $16.3 million. The presence of nitrogen causes yellow color in diamonds. Common secondary colors in yellow diamonds include greenish yellow, brownish yellow, and orangish yellow, and sometimes these modifying colors are present in combination. Yellow diamonds are the second most common fancy color. They are second to browns in terms of rarity, but they are the most popular in the marketplace.
Natural green diamonds in particular are extremely rare, second only to natural red diamonds, making them exponentially valuable. The value of natural green diamonds is typically based on rarity and not necessarily on beauty, making pure greens very highly valued, and combination greens more affordably priced. There is one exception to this general rule which applies to green diamonds that contain blue as a secondary color - Bluish-Greens, Blue-Greens, Green-Blues, and and Greenish-Blues are even rarer. The happen stance conditions that must occur in order for a blue diamond to turn green is virtually impossible, and hence these diamonds are even more highly valued than pure greens.
The blue diamond is one of the most rare fancy diamond colors, which is why this particular stone is so special.
Of the millions of diamonds mined each year, a mere .0001% can qualify as fancy colors and only a handful can achieve the top grades of Intense and Vivid. An even smaller percent are larger than one carat, let alone two carats.
The geological conditions required to yield fancy color diamonds are rare, making diamonds with naturally occurring colors scarce and highly prized. This rarity means that these diamonds command a higher market price.
Color diamonds have an amazing financial track record. The value has never decreased on wholesale level in more than 30 years. Blue and pink diamonds have doubled every 5 years of a strong economy. In the 1970's you could have bought a very high quality blue diamond for about 50K and today the very same stone would be worth between 2 and 3 million.
And the growing trend of investing in color diamonds can be proved by the big increase in color diamond grading demand. The demand has increased 102% since 1999.
Colors in diamond originate from lattice defects and impurities. The diamond crystal lattice is exceptionally strong and only atoms of nitrogen, boron and hydrogen can be introduced into diamond during the growth at significant concentrations (up to atomic percents).
Nitrogen is by far the most common impurity found in gem diamonds and is responsible for the yellow and brown color in diamonds. Boron is responsible for the blue color. Color in diamond has two additional sources: irradiation (usually by alpha particles), that causes the color in green diamonds; and plastic deformation of the diamond crystal lattice. Plastic deformation is the cause of color in some brown and perhaps pink and red diamonds.
...and now ya know!