You know, those patterns which consist of intricate loops, circles, elliptic curves and whatnot that often appear on official documents (such as this former German banknote) or frame them.
What was their purpose? I guess to prevent counterfeit, because it would have made it more difficult for forgers to engrave printing plates in the days before photocopy and home electronics, but I’m not sure.
Watermarks. Presumably because they were originally made with water, but that’s a guess. But yes, they prevent forgery because they’re easy to check but hard to create without advanced equipment.
High quality paper is often watermarked with the manufacturer’s name as well.
The fine looping lines are not watermarks. Water marks are the images the can be seen if you shine a light through the bill and a shadowy face is seen.
The fine lines are still a pretty good ani counterfit measure. You cannot produce those fine lines on most home printers. They don’t have the resolution to reproduce them.
I can’t find anything referring to them (or marks like them) in any way other than ‘ornament’ or, indeed, ‘filigree’ (even though the term is supposed to refer to metallic lacework/inlay)
You’re right in that they’re definitely not watermarks, but I don’t think you’re right about the home printers thing. These lines are from wAY before computer printers. They were intended to prevent counterfeiting to the extent that it’s difficult and time consuming to produce the metal plates of “old fashioned” printing techniques with these fine lines. The era of computer printers, with their high-res capability, have in fact made these lines less of an obstacle, which is why paper money is being redesigned these days. A computer printer can easily reproduce these lines, but it can’t make a watermark.
Thanks mks57 for that splendid reply! Now I want to incorporate “Guilloché” into my vocabulary. Can someone tell me how it is pronounced?
Just to follow up the watermark discussion with a little more clarification, true watermarks are literally ingrained into the paper while it is still wet pulp. To create a watermark, the metal screen that strains and lifts the pulp from the water bath is modified so it carries a distinctive pattern – like a logo, for example. That pattern gets permanently transferred to the grain of the pulp fibers. It has nothing to do with anything that may later be printed on top of the paper,