These standards can be found in two books, Once graded, the coin is sonically sealed in a tamper-evident plastic coin holder known as a slab.Ĭertified coins can provide an extra measure of security when buying coins, insuring that the coin is authentic, problem free and un-doctored.įurthermore, some services offer an additional guarantee that the coin has not been over graded and maintain policies to protect the buyer.Īll of the respected services grade coins according to wear, using industry standards. Certified coins, also known as slabbed coins or just slabs, are coins that have been graded by a third-party grading service.
