During the printing of a stamp, it is possible that bits of dirt or bits of paper get stuck to the printing plate or to the sheet of paper being printed. This produces accidental varieties, often in the form of small white or coloured areas. For example, if there is a scrap of paper on the sheet of paper being printed, then if and when it falls off it will leave a white space. Accidental paper folds also produce accidental varieties.
A plate flaw is a fault of some kind on the printing plate itself and will repeat until someone notices and corrects it.
I was going through a stock of Russia 10 ruble imperforates, probably all from one internal accounting sheet in Moscow, when I noticed a white area on one stamp, top right after the word MAPKA. The white area extends to the margin. This looked to me like some accidental variety resulting from something on the paper being printed. However, when I looked closely, I could see that the yellow frame line in fact continues through the white area. That suggests that there was not some bit of rubbish on the paper being printed but some fault on the plate.
Then I looked through my stamps again and found a second identical example of the fault. Well, that points towards a plate flaw. Maybe one of my readers will tell me it has already been noticed and recorded in some specialist handbook which I ought to know about …. The stamp o the left is a Normal example, the two other copies show the possible Flaw.
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