Diamonds come in a wide array of colors. Of course, the most valuable and highly desired diamonds are generally white diamonds, with “colorless” being the most desirable.
But many diamonds that come in colors other than white. These colored diamonds are also called “fancy” diamonds. Take the famous Hope Diamond for instance: this massive 45.52-karat fancy diamond is a rich steel blue in color. Deep blue diamonds are extremely rare and while the Hope Diamond is not the largest diamond in existence, it is the largest dark blue diamond known to exist.
Diamonds are formed when carbon is exposed to intense pressure and heat. The presence of trace minerals can alter the diamond’s color if they interact with the carbon during the formation process. Other factors, such as radiation, can also impact color.
Diamonds come in an array of different colors, including red, orange, brown, yellow, olive, green, blue, white, grey, black, purple and pink. Colored diamonds can be created synthetically, but the natural diamonds are the most valuable due to the rarity.
Naturally-formed pink diamonds are considered the rarest among fancy diamonds. The extreme rarity means the prices are incredibly high and they’re so uncommon that many jewelers may go their entire career without ever seeing a naturally-formed pink diamond. Similarly, red diamonds are also very rare -- so rare that it’s believed they’re actually created due to imperfections in the lattice of crystals that comprise the gemstone.
Naturally-formed blue diamonds are the second runner up in terms of rarity, but the discovery of blue diamonds in new mining regions has resulted in a greater supply of blue diamonds.
Natural yellow diamonds are also quite rare, though there has been a relatively new discovery of yellow diamonds in Arkansas. It’s important to note that truly yellow diamonds, which are formed when trace levels of nitrogen are present, are desirable and valuable. Many confuse yellow diamonds with white diamonds that have a yellow tinge; these are considered to be less desirable, but they are not true yellow diamonds. They‘re white diamonds with a yellow tone.
Another factor impacting the value of colored fancy diamonds is the intensity of the color. A fainter, lighter color is considered less valuable; a deep, rich and vivid color is more valuable.
Synthetic colored diamonds are created in a laboratory from cultures. They are exposed to trace elements to create specific colorations. Radiation tends to cause green colors. Nitrogen causes yellows and browns, while boron causes shades of grey and blue.
These diamonds are created on-demand in a lab; they are not mined and therefore, they are not rare; the price is much lower as a result.