How Do Diamonds Get Their Color?

Look for the color. Many people believe that diamonds are naturally colorless; however, diamonds are found in a variety of colors including yellow, red, orange, green, blue, brown and even black. The perception that diamonds have no color is largely a result of the value placed on colorless diamonds by consumers.

Consider the impact of light. Color is ultimately light reflected. When light enters a diamond, it does not travel in a straight line, but instead bounces back and forth inside the diamond and reflects various colors. According to Nova Online (pbs.org) when white light, which contains all of the colors of the rainbow, enters a diamond, it disperses and reflects many different colors.

Search for impurities. Colors in diamonds are due to impurities. When diamonds are colored, the color is a result of some impurity found in the gemstone. "Smithsonian" magazine explains that the element boron found in extremely rare blue diamonds is the reason for the blue color.

Nitrogen affects the color of diamonds. When some of the carbon in diamonds is replaced by nitrogen, it gives the gemstone a yellow or brownish color. These colored diamonds are considered to have nitrogen impurities.

Observe the colors caused by natural radiation and stress. Diamonds that are green or have a greenish coating tend to be affected by radiation in the rocks surrounding the precious stone. Radiation produces defects in the stone's structure, but the color tends to exist only on the surface of the diamond and rarely penetrates far into the interior structure.

Stress on the stone's structure changes a diamond's color. Diamonds that are red or pink are believed to have defects caused by stress in the diamond when the stones were traveling to the earth's surface or by tectonic forces that affect the diamond after being brought to the surface.

Investigate whether the diamond is natural or synthetically created. Devices can produce diamonds through a process similar to how the stones form in the earth. Colored diamonds can be synthesized the same way that colorless diamonds are created in a large press, which uses high pressure and high temperatures.