What is an alchemist. [Obs.] Chaucer. Philosopher's stone, an imaginary stone which the alchemists formerly sought as instrument of converting the baser metals into gold called?

philosopher — An alchemist. [Obs.] Chaucer. Philosopher's stone, an imaginary stone which the alchemists formerly sought as instrument of converting the baser metals into gold. (Webster's 1913.)

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