Where can I sell my mother's two-carat Harry Winston ring? — Gerry K.

Unlike most other high-end engagement rings, Harry Winston pieces tend to be one-of-a-kind. Your first bet should be to contact the Harry Winston company, says Michael Toback, a diamond expert at Myron Toback Jewelers in New York City's diamond district. "They stand by a lot of the items they sell," he says. "Go and see what they might offer you." You can reach Harry Winston's estate jewelry department (which handles used jewelry) at vintage-jewelry@harrywinston.com.

That should give you a ballpark idea of the ring's price. Next, get the ring and diamond appraised, making sure to specify that you're interested in the ring's retail value, not its replacement value for insurance purposes. (The two can be very different.)

Your best price is likely to a come from a direct sale to a private individual. Auction sites such as eBay provide the easiest and most convenient means of unloading the ring, but you probably won't get full value on them. If you do go that route, be sure to set a reserve price for the minimum amount you're willing to accept. Alternatively, consider using http://www.IdonowIdont.com, an auction site devoted exclusively to estate diamond ring sales, which offers the added security of holding funds in escrow.

Failing that, consider shopping the ring around a few jewelry stores. One caveat: This is a down market, and many jewelers will give you a lowball offer, says Toback. But it could be worth the extra effort. "You never know," he says. "You might find a guy who has a thing for Harry Winston and get a higher price."

— Marc Mewshaw

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