What Are Professinally Graded (or Slabbed) Coins?
A professionally graded or 'slabbed' coin is a coin that has been authenticated, graded and encased in a sonically sealed, hard plastic holder by a professional certification service. The holder affords protection from subsequent wear or damage but is not airtight and therefore will not prevent toning. Because any tampering with the holder will be obvious, it also prevents replacing the certified coin with something else.
Counterfeit and altered coins slabbed by major certification services are not unknown but are uncommon. The authenticity of a coin may be guaranteed by the company that slabbed it. Therefore, a coin slabbed by a major certification service offers some protection, especially when fakes are known to exist and the prospective buyer is not able to reliably determine its authenticity.
Some certification services will not slab coins that have been altered, whizzed, cleaned (dipping is often acceptable), artificially toned or otherwise damaged. Others slab the coin and identify the problem on the label.
Grades are opinions. The same coin may receive different grades if submitted to different services or even if "cracked out" and resubmitted to the same service. Furthermore, grading standards for some uncirculated coins have changed since slabs were first produced (1986), so a coin in an early slab may may receive a different grade if resubmitted now. The grade indicated on a slab represents the opinions of no more than a few persons who examined the coin at the time it was submitted, and not the final word on the subject. As a result, slabbed coins given identical grades may have different market values. Whenever possible, buy the coin, not the holder.
Companies that slab coins include (in alphabetical order)
ANACS (formeraly A.N.A. Certification Service but now owned by Amos Press)
P.O. Box 182141
Columbus, OH 43218-2141
Independent Coin Grading Company (ICG)
7901 E. Belleview Ave. Suite 50
Englewood, CO 80111
877-221-4ICG or 303-221-4424
International Coin Certification Service Inc. (ICCS)
Toronto, Ontario, Canada
Numismatic Guaranty Corporation (NGC)
P.O. Box 4776
Sarasota, FL 34230
800-NGC-COIN or 941-360-3990
PCI Coin Grading Service
P.O. Box 8609
Chattanooga, TN 37414
800-277-2646 or 423-485-0997
Professional Coin Grading Service (PCGS)
P.O. Box 9458
Newport Beach, CA 92658
800-447-8848 or 949-833-0600
Sovereign Entitities Grading Service (SEGS)
401 Chestnut St. Suite 103
Chattanooga, TN 37402
Prices range from $7.50 to $175.00 per coin, depending on the service and turnaround time, plus shipping costs in both directions.
The skills and equipment needed to encapsulate coins in slab-like holders can be acquired more easily than the expertise needed to accurately authenticate and grade coins. Holders from the services listed above are not the only types that appear in the marketplace. However, slabs from some "services" may not be regarded by experienced numismatists as legitimate and may not even be backed by a guarantee of the coin's authenticity. Learning about the service's reputation and soliciting other opinions about a coin's condition may save you from paying considerably more than its true market value.