Where do Natural Fancy Colored Diamonds get their color?
When browsing through the myriad of diamond jewelry online stores and retail jewelers the vast majority of diamond jewelry available is set with ‘white or colorless polished diamonds’. The industry standard for diamond grading classification has been set by GIA, grading colorless diamonds on a letter scale of D-Z…the whitest or colorless being graded as D. Towards the other end of the scale colorless diamonds become increasingly saturated with color with shades of yellow or gray, at the other end of the scale being graded as x-z.
When it comes to diamonds with a very strong color beyond this scale, the grading system changes entirely and these colors are classified as Natural Fancy Colored Diamonds. There’s very few retail stores stocking jewelry mounted with natural colored diamonds. If they do carry a large array, it is usually with treated diamonds with that are artificially colored. There are a limited number of websites today that carry a broad range of fancy colored diamond jewelry. Natural colored diamonds are relatively scarce, so where do these diamonds get their color? The natural state of rough gem quality diamond appears as a clear colorless crystal. Being the hardest substance on earth, with an exceptionally strong crystal lattice formed from carbon, there are few elements that can be introduced to diamond that will change its color significantly. Atoms such as nitrogen, boron and hydrogen are successful in being infused with diamond during its growth, the result of which produces alternative color variants. The addition of Nitrogen is responsible for yellow and brown colors. Boron is responsible for a diamond turning blue. Fancy colors in diamonds are also achieved by irradiation often by alpha particles, causing a green color, as well as plastic deformation of the diamond crystal lattice often resulting in brown and sometimes pink and red diamonds.
Black diamonds are not really black in the sense of a difference in color, but rather the result of many black inclusions giving diamond a dark black color.
In terms of commonality the most readily available are yellow and then brown, increasing in rarity the colors are as follows in descending order:
1. Yellow Diamond
2. Brown Diamond
3. Colorless Diamond
4. Blue Diamond
5. Green Diamond
6. Black Diamond
7. Pink Diamond
8. Orange Diamond
9. Purple Diamond
10. Red Diamond
Grading Natural Fancy Colored Diamonds
GIA (Gemological Institute of America) , renowned as the world’s most respected in depended grading laboratory grade color interms of Hue, Tone and Saturation.
Hue refers to the diamond's characteristic color
Tone refers to the color’s relative lightness or darkness
Saturation refers to the colors depth of color or strength.
Eight Main Colors
According to the GIA Fancy Colored Diamond Grading system, there are eight main colors hues. Red is further defined with shades of Pink as the dominant color completing the scale to eight colors. Brown and gray are not considered in the same context as the dominant eight however they are often used as modifiers for specific hues, and also used to designate a fancy main color.
Twenty Seven Modifier secondary Hues
GIA additionally use 27 Modifier secondary hues to describe variations of a diamonds main Fancy Color.
|TWENTY SEVEN MODIFIER COLOR HUES
Tone and Saturation
GIA consider tone and saturation on two different axis of color grade.
Tone referring to the light or darkenss of a color.
Sturation as being the depth or richness of color.
These terms can be confusing and need carefully understanding.