A jeweler reported that a massive emerald was swapped for a glass fake during business hours. Four people touched the gem that day: the appraiser, the clerk, the owner, and a customer. The appraiser used a jeweler's loupe. The clerk used cotton-gloved hands. The owner used a golden set of tweezers. The customer used his bare, freshly washed fingers. The detective immediately knew which one switched it. Who?
The customer
The customer used bare fingers. Touching an emerald with bare skin leaves natural oils and fingerprints on the stone, whereas the others used tools, gloves, or protective methods to avoid smudging valuable gems.
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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