A rare coin collector claimed his entire collection was stolen while he slept. Investigator Cole examined the display cases and noticed a thick layer of dust on the wooden shelves beneath the missing coins, but clean circles where the coins supposedly sat. Cole arrested the collector. Why?
The dust
If the coins had been sitting there for years to accumulate that thick layer of dust, removing them would leave clean circles. However, the dust was completely undisturbed *around* the clean spots, meaning the coins hadn't been there in months.
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: Hard. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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