At a winter dinner party, the host was poisoned. Four guests drank spiced cider: the doctor, the lawyer, the architect, and the professor. Each used a different decorative mug. The doctor's mug was ceramic, the lawyer's was silver, the architect's was copper, and the professor's was glass. The detective noticed that only the lawyer's silver mug had severe tarnish marks on the rim where the lips would touch. The detective immediately knew the lawyer was innocent. Why?
The poison reacted with silver and turned it black, or silver tarnish prevents poison from working.
Certain historical poisons react instantly with silver, causing immediate and distinct corrosion or blackening. The clean tarnish-free rim of the lawyer's mug meant no reactive liquid had touched it.
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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