A rare emerald was stolen from a high-security vault. The thief left behind a single drop of water on the pedestal. The vault has no plumbing, no air conditioning condensation, and it hadn't rained outside. How did the water get there?
Ice
The thief used an ice carving shaped like the emerald to place in the vault temporarily while stealing the real gem, or used an ice block to jam the mechanism, which later melted into a single drop.
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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