Mineral acids are acids derived from inorganic compounds. Historically, strong mineral acids like nitric acid, sulfuric acid, and hydrochloric acid were developed by alchemists and early chemists during the Middle Ages. Nitric acid (aqua fortis) is often credited to the Arab alchemist Jabir ibn Hayyan (Geber) in the 8th century, produced by distilling saltpetre (potassium nitrate) with vitriol (sulfates).