Polderpers

A literary publisher who prints short runs and sells mostly by spine. The mark lives at the foot of every book, in foil, at fourteen millimeters, and it had to hold together after the block cools and the paper moves.

An open book, drawn as two folded planes meeting at a valley rather than as a pair of curved pages. Flat planes hold a foil edge; curves do not. The stroke is one weight throughout and the valley is left open by a third of a millimeter so the block never bridges it.

The system is a set of three spine layouts by book thickness, plus the rule that nothing may sit between the mark and the foot of the book.