Note: Occasionally Proxiblog will post “On the Block,” allowing auctioneers to speak their minds about selling coins online. In this installment we feature Dave Nauert of Silvertowne Auctions, one of the highest ranked sellers of coins on this site (see our rankings to the right), giving numismatic advice to buyers, sellers and Proxibid auctioneers.

Buying coins in online auctions can be fun and exciting. A wide variety of coins usually is offered and often coins can be purchased for less than at other venues. There are, however, a few things to watch out for if you are a bidder or an auctioneer.

Make sure the auction company has expertise in the merchandise it is selling. Many auctioneers will sell anything that comes through the door without having any knowledge of the product. This may be okay when buyers have the ability to physically inspect the items in person, but it puts buyers at a disadvantage on the Internet.

The value of coins is so closely tied to condition that buyers must be able to trust grades given by the auctioneer, and also have good pictures to determine the grade. Without knowledgeable people, many auctioneers simply can’t supply this information and often will just rely on the consignor’s grades or not grade coins at all. Most auctioneers also can’t authenticate coins or detect cleaned, repaired, or doctored coins. Our coin experts at Silvertowne have been involved in the coin business for over 40 years. We look at and grade all of the uncertified coins ourselves. Problems are noted so that buyers can bid appropriately.

Auctioneers and buyers also should be aware of unreliable grading services. I recently saw a coin in an MS-66 holder that was probably an MS-60 before someone started polishing it. (Note: This is called a “self-slabbed” coin, an unethical practice by unscrupulous sellers posing as grading companies–click here for more information about that.)

By the time the “self-slabber” was done the coin it looked more like an AU-58. And then he consigned it.

The difference in value between AU-58 and MS-66 is almost $8000. The person that bought the coin in an online auction thought he got a great deal. He didn’t.

An auction company should describe self-slabbed and other coins accurately. NGC, PCGS, ICG, and ANACS are all fairly reliable grading services. At Silvertowne, when we auction coins in other holders, we always provide our opinion of the actual grade of the coin. (Note: Proxiblog advises auctioneers unfamiliar with coins to hire a local expert to write the descriptions, as Chris Fisher of Fisher’s Auctions and Appraisals does and explains in this post.)

Buying, selling and auctioning coins can be fun. And remember, don’t be afraid to ask an auction company any questions you have about the coins in its auction. Most will be happy to help you out.

Postscript: If you are an auctioneer who wants to share views in “On the Block,” leave your email in a comment. We’ll be in touch. Rules are simple: Explain your practices and perspectives as proactively as possible, as our intent is to share information to make the online buying experience pleasurable and profitable for auctioneer, consignor and buyer. “On the Block” is not a venue to challenge Proxiblog’s “Honor Roll” standards or Proxibid fees.

Proxiblog is an independent entity with no ties to Proxibid. We promote the ethics of the National Auctioneers Association and American Numismatic Association.