Stamp watermarks were security features used to prevent counterfeiting.
Creating these watermarks was part of the paper-making process. First,
the pump was put on a wire mesh screen – like a window screen – with
thin metal letters attached to it. When pressed down, the letters on
top of the screen made the paper thinner than the spaces where there
were no letters.
The first watermarked stamps were released in
April of 1895 – 125 years ago this year! The Bureau of Engraving and
Printing (BEP) took over printing postage stamps from the American Bank
Note Company in 1894. The BEP took the original dies and plates of the
1894 series and made improvements, which included adding watermarks.
But this led to unforeseen problems for the BEP…