Geoffrey Chaucer,
Chaucer's Works (ed. Skeat) Vol…
(1900)
“ He adds that there are really three philosopher's stones, one vegetable, capable of healing diseases; another animal, capable of assisting each of the five senses of man; and the third mineral, capable of transforming the baser metals into silver and gold.It is easy to see how the various metals were made to answer to the seven planets. Gold, the chief of metals and yellow, of course answered to the sun; and similarly silver, to the paler moon. Mercury, the swiftest planet, must be the shifty quicksilver; Saturn, the slowest, of cold and dull influence, must be lead. ”
