Two diamond companies have formed the Natural Color Diamond Association, an organization designed to promote the “other” stones in the diamond family.

“We want to get colored diamonds to the forefront of fashion,” says Jennifer Phelps-Montgomery, fine-jewelry manager for Michael Werdiger, one of the organization’s founders. “The notion that diamonds need to be white is old-fashioned. We need to open people’s eyes to the variety of colored diamonds. Just like people appreciate flowers of all colors, we want to educate them about the variety of colors in diamonds.”

NCDIA was formed following a successful campaign by Rosy Blue, the group’s co-founder, and Japanese retailer Kashikey, which promoted brown diamonds in Japan. The organization wants to replicate that on a worldwide level.

Among the group’s members is RTZ, owner of Australia’s Argyle mine, a leading producer of pinks and browns. Another is Louis Glick, which promotes “blonde” (yellow) diamonds.

The new organization made a big push at the 2004 Oscars, enlisting designer Randi Rahm to create three “diamond gowns”—one using chocolate brown stones, another pinks, and a third champagnes.

The group also is developing an “NCDIA” seal for retailers, to assure customers that their diamonds’ colors are natural. This is particularly important in the colored diamond market, which has been beset by treatments and synthetics.

“We are not going to talk just about the stones’ colors, but their provenance, the fact that it took 3 billion years for these stones to form and get that color,” says Sandra Arslanian of Rosy Blue. “It’s not something that can be created in 15 minutes while you are eating your hamburger.”

More information can be found at the group’s Web site, www.ncdia.com.