Jon Cronin's girlfriend would nearly cry each time she watched the ad where the guy slips his wife a giant rock on a trip to Venice. So when the Boston-based real-estate developer decided to propose four months ago, he flew her to Italy, where he popped the question in St. Mark's Square with a six-carat solitaire worth more than $100,000. "She's still in shock, I think," says Cronin, 38.

These days, bling isn't reserved for hip-hop artists and Donald Trump. Young brides from Boulder to Boston are flashing rings twice the size of what their moms once wore. The Gemological Institute of America has seen a 41 percent jump since 2000 in the number of two-carat-plus diamonds that it processes. "For a long time, the one-carat stone was basically the standard," says Carley Roney, founder of "But for a growing set of people, it's just not good enough anymore."

What's behind the zing for bling? Relentless marketing from the diamond industry, endless coverage of celebrity engagements, growing affluence at the top of the income ladder and the fact that couples are marrying later, when they can afford more. Also, Internet sites like and discount chains like Wal-Mart have entered the market, creating plenty of lower-priced options.

Fashion has also played into the trend; in the '00s, flaunting wealth is de rigueur. "Hip-hop had a lot to do with it," says Jacob & Co.'s Jacob Arabo, who supplies humongous diamonds to the likes of P. Diddy. "We seem to be in a very flashy society lately," says Petro Belezos, 36, who bought his wife a two-carat ring after she showed him a photo of a celebrity's.

Of course, not everyone can afford to splurge. C. Brown, a law student from Dallas, says he didn't want to take out a loan or borrow money from his parents when he became engaged earlier this year. Yet, "girls almost expect two carats," he says. Instead, Brown bought his fiancee a bling-ring made from moissanite, a man-made crystal that supposedly looks more authentic than zirconium. It cost just one tenth what he would have paid for the real thing. Since then, they've fallen in love with their forgery and may decide that moissanite... is forever.