Diamonds in the Rouge

Though widely perceived as colorless, diamonds are infrequently achromatic and can occur in every hue of the rainbow. In fact, color is one of the four standards for judging the beauty and worth of a diamond (the others being carat, cut, and clarity). When it comes to diamond color, there are two seemingly contradictory principles: less is more, and more is more. The fewer impurities and flaws, the more transparent the diamond and the higher the value. Yet rare colors such as blue, green, pink, orange, and black are highly desirable and even museum-worthy. A faint straw yellow will detract from a diamond's value, while a deep yellow is prized.

"White" diamonds are classified according to their degree of transparency. Most white diamonds actually contain yellow or brown tints. The Gemological Institute of America developed a scale of diamond color saturation, ranging from D (colorless) to Z (noticeable light yellow or brown). Diamond color is determined by comparing a gem to a master set. Special folded cards are also used to evaluate color. Dara Horn poetically describes how diamond color is influenced by context. Three diamonds that look identically transparent against deep black velvet reveal their differences when placed in the crease of white paper: "The first sat tarnished on the paper, throbbing a bruised and tawny color; the second glowed a dim yellow like a dying gas lamp in an old painting. The last one, exposed and revealed, blazed burning white."

[Read the entire article in my guest blog at Colourlovers.com.]