A mythical substance supposed to change any metal into gold or silver and, according to some, to cure all diseases and prolong life indefinitely. Its discovery was the supreme object of alchemy.
- ‘The philosopher's stone is red, or so the alchemists believed: ‘Red is last in the work of Alkimy,’ said Norton of Bristol in the fifteenth century.’
- ‘Combining sulphur and mercury may have been an attempt to produce the philosopher's stone.’
- ‘Alchemists, the tales go, sought to use a magical philosopher's stone to transmute lead into gold.’
- ‘Kristina continued her alchemical studies, trying to find the philosopher's stone and turn lead into gold.’