Fiscal cancel

In philately a fiscal cancel - symbol - is a cancellation on a stamp that indicates that the stamp has been used for fiscal purposes.
The stamp may either be a revenue stamp, intended purely for fiscal use, or it may be a dual-purpose stamp valid for either postal or fiscal use.

Varieties

Fiscal cancels take a variety of forms:

Pen cancels with a simple cross, initials or other markings.
Perfin or punched hole cancels.
Embossing.
Damaging the surface of the stamp using a serrated or ridged roller.
Multiple parallel cuts.
Handstamp cancels similar to the postmark on a stamp and which may be in purple or red ink rather than the black favoured for cancels of postage stamps.
Tearing or other physical damage to the stamp.

Examples:

Values

Postage stamps valid for either fiscal or postal purposes are often worth less when fiscally used than when postally used. They are not, however, necessarily more common fiscally used than postally used.