To me, this looks like a pit in the plate that has collected excess ink at the tip of the C.
tedski_tx
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Poland, Scott Nr 556 (1952) City name spelled with G instead of C.

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Aggiunto a Stamps - Worldwide — 3 anni fa — 1171 visualizzazioni

To me, this looks like a pit in the plate that has collected excess ink at the tip of the C.