The world of fancy colored diamonds is not as intimidating as some think, dealer Marc Lazar told a seminar on the topic at the recent Diamonds by JCK show in New York.

“When you come down to it, fancy colored diamonds are pretty simple,” he said. “Once you learn the terminology and become sensitive to the nuances of these diamonds, you’ll wonder why you didn’t look into them earlier … Fancy colored diamonds bring an added flavor and unique distinction to the field as white diamonds become more commoditized and consolidated.”

The only way to learn about the diamonds is to “begin transacting in them,” he said. “In the world of fancy colored diamonds, you gain knowledge by experience. There is no price list for these extraordinary diamonds. The price of whatever you buy or sell is based on supply and demand and maintaining a mental database of what’s available at what price.”

But he noted that “if you’re not quite willing to plunge [into the market] head first, most vendors understand that hesitation and may even provide you with some samples on memo in order to further stimulate your interest.”

Lazar gave the following tips for valuing fancy colored stones:

• Insist on reports from GIA or a recognized laboratory. If the report is more than several years old, get a new one, since grading standards have changed in the last few years.

• The most common color grade is “fancy,” which commands a mid price, and the most valuable is “vivid”—but “even within a single grade there can be a considerably wide range of difference from one stone to another,” Lazar explained. “I’ll always ask if the stone is a low-end intense or a high-end intense. Or I might say: ‘The stone is a 7 on a scale from 1 to 10’ describing how vivid it is.”

• Some cuts are rarer and more valuable than others. “This is partially a result of consumer taste, but more due to the fact that some cuts—such as a round brilliant or an emerald cut—retain less color than others,” Lazar said. “By definition, it’s harder to attain a higher saturation level with those cuts.”

• Clarity does not play as important a role in colored diamonds as in white ones. “The predominant value factor for colored diamonds is rarity, so that greatly overrides the clarity issue,” he said. “Many [diamonds] that have an SI₁ clarity or less will be certified with a ‘color only’ certification that omits the clarity grade.”

• When setting fancy-colored stones in jewelry, consider that the reflecting metal can enhance or reduce its color intensity. For example, he said, “Rose gold usually enhances the color of pink diamonds, but if the saturation is strong enough, platinum might provide a more sophisticated look. Personally I believe that less is more. So I follow a minimalist approach. You can use competing and contrasting colors yet still not have to use heavy metal around the stone. The advantage is that it gives you the freedom to create more unusual and delicate designs. In other words, let the beautiful diamonds speak for themselves. Let the natural light bring out their natural beauty.”

• Lazar noted that color is commonly broken down into “hue, saturation, and tone.” Hue refers to spectral colors—such as red, blue, green, and so on—that are distinct from each other. Often fancy colored stones are not just one hue, but combinations of colors blended together. When describing mixed hues, the secondary or modifying color is listed first, such as purplish pink. This means the stone is predominantly pink.

Saturation is the “intensity or quality of color in the stone … for example, if you take a bucket of blue paint and stir in some white, you don’t get a new color, you get a lighter blue.”

Tone “describes how light or dark a color is. As tone increases, so does the darkness of the stone. Tone is different from hue or saturation because it won’t affect the saturation of the diamond until it becomes so strong as to overpower it. In cold stones, such as blue color, tone will appear to be gray. In warm stones like yellow, it will look brown.”