Specimen Overprints and Perfins
When a country that is a member of the Universal Postal Union issues a new stamp, it is necessary to send a copy of it to the postmasters of each member nation so that they can tell which stamps are valid for postage, and can thus identify improperly paid mail. These copies were usually overprinted "Specimen" or "Ulramar" on Portuguese stamps. Because they were only required for distribution to the member nations, the quantity produced is always very low - generally between 250 and 500 of any given stamp.
You recently viewedClear recently viewed