watermark
Sign in to savethumb|Machine-made watermark on a 19th century letter A watermark is an identifying image or pattern in paper that appears as varying shades of light and dark when viewed by either transmitted light or reflected light. These patterns are created from variations in the thickness or density of the paper. Watermarks have historically been used on postage stamps, currency, and other official documents to discourage counterfeiting. There are two primary methods of producing watermarks in paper: the dandy roll process and the more complex cylinder mould process.
Article
10 sectionsContents
- History
- Processes
- Dandy roll process
- Cylinder mould process
- On postage stamps
- Watermarks and historical scholarship
- See also
- References
- Further reading
- External links
thumb|Machine-made watermark on a 19th century letter A watermark is an identifying image or pattern in paper that appears as varying shades of light and dark when viewed by either transmitted light or reflected light. These patterns are created from variations in the thickness or density of the paper. Watermarks have historically been used on postage stamps, currency, and other official documents to discourage counterfeiting. There are two primary methods of producing watermarks in paper: the dandy roll process and the more complex cylinder mould process.
Watermarks vary widely in their visibility. While some are easy to see, other watermarks can be covert. Aids to spot watermarks have been developed, such as watermark fluid that wets the paper without damaging it. A watermark is particularly valuable in the examination of paper goods because it can be used to date documents and artworks. Watermarks can identify sizes, mill trademarks and locations, and the quality of a sheet of paper.