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What Are Colored Diamonds?

Diamonds form deep beneath the Earth's surface. The extreme temperature and pressure in the Earth's mantle forces carbon atoms to crystallize into the hardest known surface. The purest diamonds are colorless and crystal clear. The Gemological Institute of America created a scale to determine the value of diamonds based on color, but it ranks only clear and yellowish diamonds. The more intensely colored diamonds, known as "fancies," are valued, particularly in the jewelry industry, for their rarity and intensity of color. The color of these diamonds results either from trace elements, such as nitrogen or boron, that interacted with the carbon atoms or from imperfections in the diamond's crystal structure.

Yellow Diamonds
- Also known as Canary diamonds, fancy yellow diamonds are mined all over the world, including in South Africa, Australia and Arkansas. The yellow color results from the addition of nitrogen to the diamond's carbon structure. Gemologists recognize seven distinct color grades of yellow diamonds, ranging from faint to fancy deep. The most sought-after Canary diamonds belong to the three grades with the deepest colors: fancy intense, fancy vivid and fancy deep.
Blue Diamonds
- Blue diamonds are quite rare. The blue color results from the presence of boron during the formation of the diamond. Shades of blue range in intensity from very pale blue to deep navy blue.
Other Colors of Diamonds
- Pink, red and purple diamonds are extremely rare. They're so rare that scientists remain baffled about the cause of their color. Some scientists contend that the color results from hydrogen impurities, while others believe that the color results from imperfections in the crystalline structure. Green diamonds result when uranium mixes with the carbon.
Famous Colored Diamonds
- Some of the world's most famous diamonds are colored. The Kimberley Octahedron, the largest diamond of any color, is a yellow diamond weighing an astonishing 616 carats. The Darya-I-Nor is the largest pink diamond, at approximately 185 carats. At 45.52 carats, the Hope Diamond is largest blue diamond. In contrast, the largest red diamond, the Moussaieff Red Diamond, is a measly 5.11 carats. The Kahn Canary, found in 1977, brought fame and stature to Arkansas diamond mining. Hillary Clinton has publicly worn this stunning diamond numerous times.

Rocks & Minerals