Why go to an auction? First of all, jewelry auctions offer unique pieces that may not be available through regular channels, and some of those items may fit perfectly into your inventory. You can also learn a lot by attending auctions. They are wonderful training grounds for anyone interested in establishing an estate department.

But not everyone who makes a winning bid comes out a winner. When the “winning” bid is too high, the winner might feel more like a loser. If you plan to take part in some auction action, make sure you know what you’re doing. Here’s how to begin:

Inspect the property. Don’t rely solely on the photographs and descriptions in auction catalogs. Photos may be enlarged or color-enhanced, and only lot information in boldface type is guaranteed. Examine in person the pieces that interest you, using a 10x loupe. (Other tools include penlight, notebook, pen, and gemstone cleaning cloth.) If you can’t see the piece yourself, engage the services of a professional gemologist/appraiser to do it for you. At the very least, obtain a condition report from the auction gallery. (The gallery, of course, wants to sell the item, so expect a positive report.)

Look for cracks or chips in gemstones, repaired areas, solder lines, damage to the frame, elements not original to the item, and missing stones. Examine the signature, metal stamp, hallmark, or trademark to determine authenticity. While you’re inspecting, ask for other opinions—from the gallery representative behind the counter and even from people nearby. Remember, at auction you’re buying “as is, where is.”

Important diamonds and gemstones should have a laboratory report fully describing the material. Certificates for colored stones should list a color origin or a country of origin as well as clarity and enhancement information.

Study the catalog. In addition to pictures and descriptions of the items to be sold, some auction catalogs include histories or biographies of designers and manufacturers. Such information can enhance your working knowledge and aid decision-making. Some catalogs include a useful glossary of terms. A Butterfields catalog for a recent auction of jewelry and timepieces, for example, includes brief definitions (as they apply to jewelry) of “Georgian,” “Victorian,” “art nouveau,” “Edwardian,” “art deco,” and “retro.” The glossary also defines the terms “antique,” “date/origin,” “attributed,” “signed/stamped,” and “style” as they are used in the catalog. “Style,” for example, is defined as a “term describing jewelry that, in our opinion, was produced as a facsimile of an earlier period.”

Remember that presale estimates for all lots in the catalog are approximate guides to current market value and should not be interpreted as floor prices. Items sell below estimates as well as above estimates.

Do additional research. After you inspect the piece you’re interested in, check the prices of similar items by looking at recent catalogs—go back three to six months—that include selling prices. Research other auction galleries within your geographical area for similar pieces and selling prices. Study price guides, price lists, and reference guides to determine a likely price range for the piece you plan to bid on. Conduct additional research by visiting retail stores, pawnshops, antique shows, Web sites, and antique jewelry stores.

Finally, attend at least one “warm-up” auction sale to get the feel of the gallery. Take notes, observe bidding procedures, and strike up conversations with professionals and dealers.

There also are plenty of opportunities for ongoing education in antique and estate jewelry. For starters, there’s Warman’s Jewelry: A Fully Illustrated Price Guide to 19th and 20th Century Jewelry, Including Victorian, Art Nouveau, and Costume by Christie Romero (2nd ed., 1998, Warman). It’s an affordable book with an outstanding timeline. An Illustrated Dictionary of Jewelry by Harold Newman (Thames & Hudson, 1994) gives definitions of common and not-so-common jewelry terminology. Auction Market Resource, published twice a year, provides updated gemological and auction sales price data.

Consider attending seminars that take place in conjunction with national and regional jewelry shows. Even if you’re not registered for the show itself, you may find that the educational events are held in rooms outside the jewelry exhibit area. Alumni chapters of the Gemological Institute of America hold frequent meetings on a variety of gem and jewelry topics, and annual meetings of major appraisal organizations offer discussions of relevant topics. The Southern California Antique & Period Jewelry Seminar is held in the spring, and the Antique & Period Jewelry & Gemstone Conference takes place every year in Providence, R.I. Auction houses frequently present lectures and extended seminars, and many museums offer special exhibits and lecture programs on jewelry and jewelry-related topics. Antique shows often have lectures and seminars by experts.

Know the rules. Read the conditions of sale at the front of the catalog. Almost every auction gallery will have a limited condition statement similar to this one from Beverly Hills Auctioneers in California:

All statements contained in the catalog or in any bill of sale, invoice, or elsewhere to authorship, period, culture, source, origin, measurement, quality, rarity, provenance, importance, exhibition, and literature of historical relevance or physical condition are qualified statements of opinion and not representations or warranties.

Recent catalogs have included notices warning customers that the color or clarity of gemstones and diamonds might have been enhanced. This one is from Boston-based Skinner:

Purchasers are reminded that colored stones and diamonds may be enhanced by using one or more techniques, including but not limited to: clarity enhancement, resins, and heat treatments. Skinner makes no warranty express or implied to the buyer as to whether a natural stone has been enhanced.

Be aware of the gallery’s policy on bid increments. Wechsler’s in Washington, D.C., for example, allows increments in multiples of $25 when the bidding level is less than $500. The multiple rises to $50 when bidding reaches $500, goes to $100 when bidding reaches $1,000, and jumps to $500 when bidding hits $5,000. When the bidding level exceeds $10,000, increment multiples are at the auctioneer’s discretion.

You’ll also need one “rule” of your own. Set a ceiling on your bidding, write the number next to the appropriate catalog entry, and don’t exceed that limit. Otherwise, you risk getting caught up in auction fever, which can lead to a bad case of buyer’s remorse. Be sure to factor in the buyer’s premium (and sales tax, if applicable) when determining your final figure.

Final details. Know the payment policy of the gallery and prepare accordingly. Cash, a cashier’s check, a personal check (upon established credit), or a credit card may be acceptable, but many galleries accept only cash, cashier’s checks, or money orders. Make arrangements to get cash quickly, if required. Sales tax will be added unless you produce your state’s tax exemption number.

Usually, you must take jewelry with you after the sale or pick it up within 30 days. If you don’t retrieve an item within the specified time, the gallery may levy a storage charge. Also, keep in mind that if the gallery packs or handles your lots, it does so entirely at your risk.

In the event you’re unhappy with your purchase, reread the “Conditions of Sale” under the heading “Limited Right of Rescission” for return policy and procedures.

Finally, here’s a little-known fact that can be a great advantage for retailers: Some galleries will entertain offers to purchase “buy-ins” (pieces that did not sell), and sometimes a consignor will accept such an offer.

Gail Brett Levine, G.G. is an independent appraiser, consultant to the trade, and publisher of Auction Market Resource.