The hobby of stamp collecting makes extensive use of experts committees and individual experts.
An example of what may be considered by an experts committee for a cover would include:
The cover itself:
Are there any repairs to the cover
Sealed tears
Stains removed by bleaching
Cutting down one side of the envelope to remove a torn edge where the envelope was opened
Erased pencil marks written by earlier stamp collectors
Is the cover faked:
Is the p ...
