Silver test

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Silver test

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The Silver test is what the Anglo Saxons used for testing the special stamp papers their Post Office introduced to prevent a re-use of postage stamps after washing off the cancellations.

In the coating applied on the surface of the stamp, the chalk reacts to a silver object, a coin or so...


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Several stamps of the UK and the Commonwealth exist both on "normal" paper as on "chalky" paper with the Chalky version often getting a much higher price...



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Of the 3 stamps only the utmost right stamp had a coating!


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But what had happened to the back of the stamps????
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