Ancient Gold 'Coin?' From Southern Europe, No Reserve

This is from my uncles estate who served in southern europe during & just after W.W. 2. He purchased it in 1945-46, it was once mounted into a ring, I believe. It was tested to be high carat gold, but I'm unsure exactly what it is. It is appx. 2.8 mm in diameter (not completely round) and weighs appx. 2.0 grams, a U.S. dime is shown for scale. There are light marks on the front, a small crack on the edge and a white residue on the right side I prusume from being mounted. $2.95 first class  insured shipping within the USA - insurance extra if desired, $3.75 uninsured shipping outside of the U.S.  - sorry, I have been told that I cannot ship this to Italy or Greece. I combine lots to save shipping, thank you for looking.