The Science Behind the Colors of Diamonds
A diamond is not always colorless or white in order to be valuable. There are many minerals, including nitrogen and boron, that can affect the hue of a gemstone, as well as its value, as a result of their presence.
Among the many colors of diamonds, there are pure white diamonds, soft pinks and blues, as well as brilliant hues like purples and reds in the most vibrant of hues. Every stone, regardless of its color, possesses a unique composition of chemical elements that can be used to determine its rarity, value, and desirability, depending on the composition of those elements.
The most common diamond color is white, which falls into the widest spectrum of colors on the Diamond Grading Scale, which begins with "D" color, which signifies a diamond that is totally colorless, and ends with "Z" color, which indicates a diamond that appears pale yellow or brown.
During the spectrum of this diamond, the variable is the element nitrogen. In a diamond of D color, the nitrogen is not present (or is present in only microscopic amounts) nor is there any other element present in the diamond. In general, the higher the amount of nitrogen present in the diamond, the deeper the color will be, and the diamond will move further along the color spectrum as a result.
The vast majority of white diamonds that are mined today have a high nitrogen content, which means that they are classified towards the lower end of the color scale as they are classified as white diamonds. A diamond of color D–F is considered to be a rare stone, therefore it will command a more expensive price than a diamond that falls towards the end of the color spectrum, which is less rare.
Diamonds that have been colored usually contain impurities within the chemical composition of the diamond, as well as structural defects. It is believed that nitrogen is incorporated into the carbon crystal structure of yellow diamonds, causing the diamond to appear yellow. It is these nitrogen impurities that give diamonds their yellow color since they modify light and absorb a portion of the visible spectrum that is blue.
When the stone contains a large amount of nitrogen, the diamond ceases to be a M-Z colored diamond and turns into a fancy colored diamond, when there is a significant amount of nitrogen present within the stone. In order to grade fancy colored diamonds based on their color-grading scale, the following four categories are used: Fancy Light, Fancy, Fancy Intense and Fancy Vivid. There is an increase in the value of a stone as the color concentration within it increases.
In the Earth's crust, boron, a rare element, is responsible for the creation of blue diamonds. The majority of blue diamonds are modified with a gray secondary tone or uneven saturation with areas of colorless windowing, making them extremely rare when it comes to natural blue diamonds with exceptional saturation and brilliance.
Pink, Red & Other Colored Diamonds
The other colors within the Earth, such as green, purple, and orange, are caused by natural radiation as well as common elements within the planet itself. The presence of colored diamonds in nature is truly an anomaly, as they are truly unique.