Alchemy, an ancient experimental science, dealing mainly with metallurgy, that was the forerunner of chemistry. In the Western world, alchemy was established as a branch of science by the Greek scholars of Alexandria, Egypt, in the early Christian Era. In the tradition of the period, which interpreted all knowledge in philosophical terms, alchemy became associated with astrology, the belief that events on earth were controlled by the planets and stars.

The alchemists invented many procedures and types of apparatus used by modern chemists. Egyptian jewelers were already highly skilled in metalworking, using alloys of base metals resembling gold and silver to produce cheap jewelry. This ability to imitate precious metals may have been the inspiration for the idea that base metals, such as iron and lead, could actually be transmuted, or transformed, into gold and silver. Many alchemists of the Middle Ages used deceit to convince customers that they had succeeded in transmuting metals.