Hey guys,
The blue ink on these PIEDMONT Factory #42 cards varies all over the place. Many of them are very light blue, while others are a darker blue (typical of PIEDMONT cards).
These PIEDMONT cards, and the UZIT cards were printed in the last production runs of the T206 set (circa Jan - Feb 1911). Both these backs exhibit this blue ink variation.
It has nothing to do with environmental or chemical or human tinkering with these cards. American Lithographic, for whatever reasons printed some with their normal blue
ink, and others with a "diluted" blue ink.
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And, two semi-dark blue ones......
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And, two light blue cards.....
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TED Z
T206 Reference
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