Substrate Feature: The Watermark

Even with the implementation of color-shifting ink, segmented security threads, ultraviolet inks, and polymer banknotes the watermark (at the insistence of Interpol) remains the primary security feature on most notes amongst all the world’s major banks. How such a simple feature has become so timeless and the staple amongst the plethora of currency security features I intend to investigate in this article.

A watermark is an image in a banknote (or any type of secure document) that is easily identifiable when light is transmitted through the substrate. When light is transmitted though the banknote the image is created by density variations in the substrate where the watermark is intended to appear. The image is usually a pattern, portrait or the denomination of the banknote itself.

To understand how this incredible security feature has lasted centuries in the banknote world it is first necessary to understand how it is made. There are two main processes that are used in the creation of watermarks: the Dandy Roll process and the Cylinder Mould process.

Created in 1826 by John Marshall the Dandy Roll process, according to Philip Megg’s A History of Graphic Design, is when a watermark is created by impressing a water-coated metal stamp (the dandy roll) onto the paper during manufacture. On the dandy roller would be something like a window screen, only more robust. Within this screen would be the intended image made by intersecting lines of laid wires and upon those chain wires. The laid wires (being underneath the chain wires) create a faint impression on the paper pulp, while the chain wires create a greater impression. The dandy roll is rolled along the pulp when it is still fairly wet so the roller can make an impression. As the paper dries, the watermark appears.

The Cylinder Mould watermark can, unlike the Dandy Roll, create shading from light to dark almost creating a three dimensional image. The image is created by areas of relief on the roll itself. Created in 1848, the Cylinder Mould process is the most effective and widely used today.

First of all, the watermark is incredibly inexpensive to create. It costs far less to insert a watermark into the banknote substrate than to cover the note with iridescent inking features, or complex UV ink designs. Since banknotes are already expensive for governments to produce, any cost reduction is sought after.

Secondly, from the descriptions above one can tell that the watermark is not an easily recreated feature. The process is complex, and for a counterfeiter to create an accurate watermark would be incredibly time consuming and require a great deal of skill and resources. This is why one often times finds counterfeit notes that have the “watermark” printed or drawn on the reverse side. But to a trained eye, this is easily discernable as a forgery.

Another reason why the watermark has endured for centuries as the staple security feature among banknote designers is that a person with limited knowledge of banknotes can easily discern their authenticity. For instance, a $5 United States Federal Reserve Note that has been raised to a higher denomination can be instantly recognized, as the denomination is the watermark. This identification process would take no expert.

The simplicity, cost and relative complexity of the watermark has made it the go-to security feature for banknote makers around the world. Not only is it a security feature, but another opportunity for nations to include in their money what is held dear. Whether it is the Jersey Cow’s head of the States of Jersey or Benjamin Franklin of the United States, the watermark conveys a message and also keeps a simple and yet secure hold over a nation’s money supply.