New Diamond Substitute

Feb. 8 -- Fashion-minded females from around the country flock to New York’s Canal Street — the Mecca for counterfeit chic — to buy knockoffs of the latest designer purses, sunglasses and watches.

No longer regarded as inferior copies, the fakes have become fashionable. Even the glamorous Samantha from HBO's trend-setting Sex in the City endorses them: "Oh who cares," she tells her doubting friend Miranda in one episode, "all that matters is what it looks like."

If fake is in, a lot of men may be asking themselves, "Why buy a woman a real diamond when there are substitute stones that even fool the experts?"

When cubic zirconia first became popular in the early '80s, it fooled a lot of people. And it cost less that $5 per carat. However, cubic zirconia doesn't sparkle quite like a diamond, and over time it gets scratched and loses its luster.

But now there is a new stone called moissanite that is almost as hard as a diamond and even more brilliant. It's a manmade version of a mineral first found in a meteorite 100 ago. At roughly $600 a carat, it's about 1/10 of what diamonds cost. Best of all, it fools a lot of the professionals.

Click here to compare close-up pictures of a diamond, a cubic zirconia and a moissanite. ABCNEWS.com users tried to guess which one was the genuine article.

Nearly 70% of the voters guessed the wrong stone. Ring number three is the real diamond and number two, with 45.7% of the votes, is the moissanite.

But ABCNEW.com users were not the only ones fooled.

20/20 took a 1-carat moissanite ring to 10 jewelers in the Washington, D.C., area and asked them to examine it and make a rough estimation of its value. Five of them thought the moissanite ring was a real diamond worth thousands of dollars. It even tricked an electronic diamond detector.

The is a visible difference between the two stones under magnification. A moissanite has double refraction lines and a diamond has single lines. But if a jeweler's not looking closely through a microscope, he is is likely to be fooled.