Stamps that come in 2 parts.
Part A is the Talon, Part B is the Guia
Sometimes the stamp designs extends from stamp to talon.
Sometime the talon had a different but related design printed sideways in relation to the stamp design.
Unused Mexican revenue stamps should be collected with the talon still attached.
The talons of used Mexican revenues were usually detached at the time of use. Normally, the stamp was attached to the document, while the talon was attached to a receipt or record book.
Predictably, used stamps with talons still attached are more valuable than those without talons.
Mexican revenue stamps are listed in the Revenue Stamps of Mexico by Richard Byron Stevens.
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