BLOCK (PHILATELY)

In philately, a block is a group of postage stamps still attached to each other. Blocks are of interest not only because they are rarer than individual stamps, but they also preserve relative positions of stamps as they were originally printed, information that is crucial to understanding how the stamps were produced.

Blocks of stamps from the edges of the original sheet or pane often include sections of the sheet's margin, which may have a wide variety of information. Plate blocks, for instance, include the part of the margin where the serial numbers of the plates are found, while arrow blocks preserve the guide lines used by line up the sheets for perforation or other production steps.

Ironically, although blocks of rare stamps are highly valued, a block's price may be so high that no buyers can be found, leaving the owner with the agonizing prospect of breaking up the block, so as to be able to sell the stamps individually. In some cases, a dealer will publicize plans to break up a famous block, in the hopes of that someone will come forward to save the block from destruction.