Coil Line Pairs

Coil Line Pairs or Joint Line Pairs are created on rotary press printed coils at the point where the two curved plates meet to create a rotating cylinder that was needed to print on a continuous roll of paper. Ink would fill in the joints between these plates leaving two joint lines for every rotation of the cylinder as the stamps were printed.  Depending on the plate that the coil stamp was printed from a joint line pair generally appears every 15 or 17 stamps.