Before revision: Two important sources from the Middle Ages on chemically colored metals are the Mappae clavicula, which was dated between the 9th and 12th centuries, and Theophilus Presbyter's work De Diversis Artibus, which was dated to the 12th century.
After revision: Zosimos of Panopolis, a Greek-Egyptian alchemist who lived in the late 3rd and early 4th centuries,is also extremely important, since to him the attributed texts are considered to be the oldest written recipes for chemical coloring of URLTwo important sources from the Middle Ages on chemically colored metals are the Mappae clavicula, which was dated between the 9th and 12th centuries, and Theophilus Presbyter's work De Diversis Artibus, which was dated to the 12th century.