Diamond color

History and Grading of Diamond Color

Color grading performed by London Diamond Syndicate
Early grading systems lacked standard nomenclature and consistency
Early grading scales included III and AAA
Numerous terms developed to describe diamond colors
Diamonds occur in a variety of colors due to impurities or defects
Diamonds classified into Type I and Type II based on impurities and light absorption
Type I diamonds have nitrogen impurities, resulting in yellow to brown tint
Type II diamonds have no measurable nitrogen impurities and absorb in a different region of the infrared

Type I diamonds have nitrogen atoms as the main impurity
Type IaA diamonds have nitrogen atoms in pairs, no effect on color
Type IaB diamonds have large even-numbered aggregates of nitrogen atoms, yellow to brown tint
Type Ib diamonds have dispersed nitrogen atoms, intense yellow or brown tint
Type II diamonds have no measurable nitrogen impurities, absorb in different region of infrared
Type IIa diamonds can be colored pink, red, or brown due to structural anomalies
Type IIb diamonds are usually light blue and contain scattered boron
Green diamonds caused by GR1 color centers in crystal lattice due to radiation exposure

Majority of mined diamonds fall between white and pale yellow or brown
More intense color diamonds termed fancy color diamonds
Colorless and vivid color diamonds are the most valuable
Diamonds in the normal color range graded using a standardized scale
Colored diamonds graded using separate systems
Yellow or brown color diamonds more intense than Z considered fancy colored diamonds
Grading of colored diamonds includes a list of 27 color hues

Value of fancy-colored diamonds determined by rarity and intensity of color
Fashion trends can affect the value of fancy-colored diamonds
Pink diamonds saw an increase in value after Jennifer Lopez received a pink diamond engagement ring
Fancy-colored diamonds, such as the deep-blue Hope Diamond, highly sought-after and valuable
Colored diamonds valued based on clarity and color
High-color diamonds more valuable due to rarity and consumer demand
Near-colorless grade diamonds more cost-effective than colorless grade diamonds

Diamond clarity is another important factor in evaluating diamonds
Diamond enhancement techniques can affect the color of diamonds
Notable diamonds that have gained fame and recognition
Various organizations, such as GIA and AGS, play a role in diamond grading and certification
References and further reading materials available for more information on colored diamonds
GIA Color Scale developed by the Gemological Institute of America
Importance of diamond color in evaluating diamond quality
Understanding diamond color essential for informed purchasing decisions

Reference	URL
Glossary	https://harryandcojewellery.com.au/blogs/glossary/diamond-color
Wikipedia	http://en.wikipedia.org/wiki/Diamond_color
Wikidata	https://www.wikidata.org/wiki/Q723995
Knowledge Graph	https://www.google.com/search?kgmid=/m/05cbbq