Necklace with coin of Constantine the Great

A necklace containing a coin of the Roman emperor Constantine "the Great", who ruled 307 - 337 AD. The reverse of the coin features the god Jupiter standing left, holding Victory and a sceptre, an eagle is at his feet. The coin was minted at Thessalonica, now Salonika in Greece, and measures 23.5mm. The bezel is silver and the coin is strung on leather. The coin is in nice condition.