Expertization

Expertization is the process of authentication of an object, usually of a sort that is collected, by an individual authority or a committee of authorities.

The expert committee will examine the collectible and issue a certificate typically including:

Some experts will apply an experts mark, signature, or similar marking to the item to attest to its genuineness.

Expertization is particularly common with valuable philatelic items, some of which are so often forged that they may be unsaleable without an expert certificate confirming that they are genuine.

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