Gypsum is naturally abundant and has been used for a long time. The Greek Theophrastus first identified the natural occurence, properties and usageof gypsum in c. 300 BC. A Persian doctor named Abu Mansur Muwaffaq is one of the first to use gypsum for plaster of Paris in 975. In the Middle Ages, gypsum was used as an illness deterrent and was believed to be able to cure insomnia. Gypsum was first discovered in the modern world by a German man named Martin Klaproth in 1789.