Alchemy was first mentioned in Egyptian mythology.  The Goddess, Isis, is said to have coerced the secrets of gold from an angel who desired her.  These secrets were written in codes and symbols, and later became the science of turning ordinary metal into gold by repeated burning at high temperatures.  Because of the seemingly miraculous change that occurs, it is also associated with magic.  Some legends also suggested that alchemy was used in the search for immortality.  The myth was that a drug could be created from gold, and ingested, which would make one immortal.  A symbol of Alchemy is the transformation of the caterpillar into the butterfly; a death and rebirth.