An interesting numismatic piece. An Austrian 10-pfennig coin from 1916 with a diamond-shaped overprint featuring the Model 27 eagle (introduced as the national emblem in 1927) on the reverse.
We are not aware of any other issues with this type of overprint. Perhaps in this case, the coin was used to test the die featuring the eagle.
The surface is protected with varnish.
Dimensions of the overprint: 3 x 3 mm.
