In addition to a 1 Lira coin, these coins are among the last silver coins minted for circulation in Turkey. They're .500 silver. They haven't seen much circulation though, they'd been legal tender here until 1960.
They're very famous of having weakly struck "50 KURUS". Even mint state examples show some weakness in the strike. I believe it's because of the design, the "50 KURUS" design/part or whatever it is called in English, is rather thin.
My guess says it's a post mint damage. Or someone thought it may be nice to remove an already weak part of a coin and makes a novelty item. Chances are, it can still be a Grease Filled Die
(they're relatively common in 1940s-1950s Turkish brass coinage) but still, just like in England, error coins does not command a premium here in Turkey.
Anyhow, I hope this helps a little bit.
Edited by molydeii
02/21/2021 4:50 pm