How any diamond behaves in light is critical to its success as a desirable stone. Consumers may not be able to articulate the nuances of a diamond’s light performance, but they know what they like. “Light performance is important to ensure that a diamond is visually pleasing to the eye,” explains Marc Knobloch, vice president of New York-based wholesaler Aron Knobloch Inc. Diamonds and Jewelry.
Yet there are key differences in light-performance expectations between colorless diamonds and their colorful counterparts. Whether the latter are color-treated or natural fancies is a consideration as well.
“In the past, discussions of light performance in color-treated diamonds did not come up,” says Jaywant Salunkhe, manager at Lotus Colors — a New York-based midstream vendor of color-enhanced diamond products. “But lighter shades will always be more brilliant than darker shades.”
So even if there’s no conversation about light performance directly, he continues, “we regularly discuss the effect of deeper shades on brilliance with our clients.” While the type of treatment has no effect on light performance, the resulting color does, he adds.
When it comes to optimal light performance, the goal of cutting colorless diamonds is to maximize brilliance. However, fancy-colored stones require a different approach.
“The goal of fancies is to achieve the right balance of color and light reflection,” says National Color Diamond Association (NCDIA) president Alan Bronstein. The fancy-diamond cutter must fuse science with art, judging each rough individually at the cutting wheel, he continues. “A cutter’s role is to balance in any way possible; to create maximum brilliance with maximized color.”
A fancy wouldn’t be cut to Ideal Cut proportions, Bronstein explains, as it may risk washing out the color. Since no two stones are alike, expert cutters begin their work on fancies experimentally, based on their knowledge of the particular rough; they may lower a pavilion slightly or raise the crown to optimize the desired color. Their aim is to create a stone with a combination of good light reflection and enough brilliance — not one that’s opaque or too dark.
That need to strike a balance, Bronstein points out, “is a completely different perspective on light performance [than] the goal of colorless diamonds.”
Salunkhe further contrasts those goals with that of color-treated stones. “In color-treated diamonds, there is no need to [cut them with the aim of making] them deeper in color. All the colors are already pretty intense. Usually, people are focused more on the color than the cut when buying color-enhanced diamonds.”
Still, he says, “that doesn’t mean cut is not at all important, because the better the cut, the more brilliant the diamond.”
With a variety of factors — besides price — keeping the color-treated niche salient, reliability in the marketplace tops the list.
Natural fancy-colored diamonds are rare and difficult to source consistently, Salunkhe notes. “Color-enhanced diamonds can be supplied in precise shapes, shades and sizes regularly.”
Frequently, the consumers who buy color-treated diamonds already own colorless diamond jewelry and want something unusual, according to Vivek Mishra, director of the diamond division at US-based wholesaler Stuller. “Treated color diamonds provide an affordable alternative for consumers aspiring to own a natural fancy-color diamond. They also appeal to fashion-forward customers looking to add a splash of color in combination with white diamonds to a piece of jewelry.”
Knobloch believes a consumer’s subjective response to a diamond is what ultimately determines whether they buy it.
“Everyone judges for themselves what they perceive as beautiful,” he says. “If a diamond is considered to be beautiful to the viewer, then it is the right diamond for them.”
Diana Jarrett is an award-winning gemologist-journalist who has been contributing to both consumer and trade publications for nearly 15 years.
Image: GuoGuiyan BackgroundsArticle from the Rapaport Magazine - November 2017. To subscribe click here.