Stitch watermark

A stitch watermark is an unintentional mark on some mid-19th Century papers. It is one or two horizontal series of short lines much line modern bulldozer or tank tracks. Like watermarks, it will often require watermark fluid or equivalent to detect. They are the result/artifact of connecting the ends of fine wire mesh sheets to make the continuous belts used in the papermaking process of the time.

A modest premium is given for stamps found with stitch watermarks.

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