Wikipedia
Muvaffak
Abu Mansur Muvaffak Harawi was a 10th-century Persian physician.
He flourished in Herat (modern-day Afghanistan), under the Samanid prince Mansur I ibn Nuh, who ruled from 961 to 976.
He was apparently the first to think of compiling a treatise on materia medica in Persian; he travelled extensively in Persia and India to obtain the necessary information.
Abu Mansur distinguished between sodium carbonate and potassium carbonate, and seems to have had some knowledge about arsenious oxide, cupric oxide, silicic acid, and antimony; he knew the toxilogical effects of copper and lead compounds, the depilatory vertue of quicklime, the composition of plaster of Paris and its surgical use.