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works of his believed to be from the 3rd century

primarily remembered for his various descriptions of elements and minerals, most particularly his descriptions of a method of producing silver,[1] and of a substance he had created, which he called a 'fiery poison', and which, judging by his account, was arsenic trioxide, a highly toxic amphoteric oxide.

Agathodaemon's discoveries exist as part of the foundations for later use of poison, as arsenic and related substances were used regularly in later centuries as means of poisoning and murder.