An alchemist is someone who practices alchemy. Alchemy is a form of science dating back to medieval times that concentrates on chemical science and speculative philosophy. It is also used to explain mysterious transformations.
Some of the goals of an alchemist include the transformation of base metals into gold, discovering a cure for disease and being able to indefinitely extended life. Alchemists are believed to be able to change or transform physical objects into other things in very impressive or mysterious, almost supernatural, ways. Before being practiced in 12th century Europe, alchemists could be found across the ancient world from China to India, Greece and Egypt during the Hellenistic period.