De la rue printed these stamps until 1865,afte which they were printed in Turin by the state plant. Identification by the cancel is maybe ok for late usage of the stamp.
Perforations in the London printings are more pecise with better centering.
*mint stamps:
The gum is distinctly different .In the London printing it is less thick and shiny.Not the characteristic streaks,sometimes dark in color caused by the thickrning of the gum visible in the Turin printings.
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The most interesting detail is looking for the security colorless varnish overprint on the paper.This was applied by de la rue on the paper before printing.As time went by this varnish yellowed and shows up like dots of yellow more or less even over the stamp.Below your first stamp where the pic was enhanced showing the yellow dots.So we can say that your first stamp is from the London printing.
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From an Internet seller. Biondi cert. London printing.
notice the yellow spots. (pic enhanced).
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Another example. Enhanced on the left.Normal lighting of the same stamp on the right.(London printing).
Posted 03/06/2020 6:05 pm
