A rare coin collector was found murdered in his locked study. On his antique oak desk lay a magnifying glass, a pair of cotton handling gloves, and an open coin album. A single golden coin rested on the desk blotter. Detective Thorne inspected the coin and noticed it was dated 45 BC. Thorne instantly knew the coin was a counterfeit, even before testing the metal composition. Why?
Coins minted before the Common Era would not be marked 'BC' by the ancient mint.
Ancient Romans or civilizations minting coins in 45 BC would not stamp 'BC' on their currency, as they did not live with the foresight of numbering years relative to a future calendar era.
About this riddle
Detective riddles are tiny mysteries. Look for the detail in the story that does not fit; it is usually the clue that solves the case.
Difficulty: Medium. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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