Watermark finder

from Wikipedia, the free encyclopedia

By watermark finders , stamp collectors understand various methods and devices that detect watermarks in the paper of postage stamps.

determination

Beginners can often find it difficult to identify watermarks. Most of the time, the existence and confirmation of the correct watermark is just another indication of the authenticity of the brand. With some stamp issues, however, the possible differences in the watermark have a considerable influence on the value. B. Scandinavian brands, collecting is strongly advised taking this criterion into account.

For all methods of watermark determination , the reverse side of the stamp must be free of paper scraps, folds and other contamination.

The simplest method for determining the watermark is to look at the mark from the back under different lighting, whereby incident light, transmitted light and changing the viewing angle can make good results possible in individual cases. For example, the older postage stamps of the Federal Republic of Germany from 1949 to approx. 1963 have 5 different watermarks, which are mostly recognizable without aids.

Petrol bowl

Another fairly simple method is to place the stamp face down in a small black plastic bowl (commonly known as a watermark finder ) filled with pure gasoline so that you can identify and classify its watermarks. Alternatively, place the stamp face down on a black plate and sprinkle gasoline on the reverse.

Danger:

  • It is essential to use chemically pure gasoline (pharmacy), as impurities may damage the stamps!
  • Among other things, gasoline is poisonous !
  • On some stamps, however, a petrol-soluble ink was used for the face . However, this is usually mentioned separately in the stamp catalogs .

As an alternative to gasoline, there are other liquid watermark finders on the market that are more environmentally and health-friendly.

Morley-Bright

The watermark finders from Morley-Bright are based on the ingenious and simple fact that a colored liquid is pressed into the depressions of the watermark under slight pressure and thus makes it visible.

Inst-a-Tector

This variant is ideal for the determination of watermarks on loose stamps up to a size of 35 × 42 mm. It is a pencil case with a plastic plate in the bottom and a sealed sachet with ink under a glass plate in the lid. The stamp is placed face down on the plate and the folder is closed. Carefully apply light pressure to the outside of the pencil case. As a result, the ink only collects in the depressions in the paper and the watermark becomes clearly visible. This handy and, with a little practice, safe and easy to use device is also ideal for on the go.

Roll-a-Tector

With this variant, the watermark of a postage stamp can be checked on a receipt. It does not have to be removed from the paper for determination. In contrast to the Inst-a-Tector , the image of the watermark is retained for a longer period of time.

Tabletop devices

Illuminated optical watermark finders have been available as small tabletop devices for around 20–30 years. With these, the stamp is placed with the back facing up under a transparent plastic plate and pressed on. With the right incidence of light, the brand's watermark and often other abnormalities appear in the paper (e.g. repairs). These devices work without any chemicals or auxiliary materials and allow a quick determination.

Various providers in Germany offer these devices under the names Letterscope, Stampscope or Signoscope (watermark finder) for prices between 50 and 150 euros. You can build such devices yourself without any problems.

literature

  • Wolfram Grallert: Lexikon der Philatelie , Phil * Creativ, Schwalmtal 2006, 3rd unchanged edition 2015, ISBN 978-3-932198-38-0 , Article: Watermark Finder .
  • Michel. Germany catalog 2010/2011. Schwaneberger Verlag, Unterschleißheim 2010, ISBN 978-3-87858-045-4 , section: Watermark , page 16. (This section is also available in many of the publisher's stamp catalogs.)