Side B: Round the edge is another inscription which appears to read [in English equivalent letters] the word or phrase: DOGNOCEN… The central design has worn too badly to identify.
The metal looks to be brass, but is also non-magnetic. The alphabet used appears to be either Greek or possibly Russian.
Diameter: about 23mm Thickness: perhaps 0.5mm Weight: unknown, but very thin and therefore extremely light-weight.

Thanks.
ozmy19