Alchemical studies produced a number of substances, which were later classified as particular chemical compounds or mixtures of compounds.
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Aqua Fortis - nitric acid, can be formed by 2 parts saltpetre in 1 part (pure) oil of vitrol(sulfuric acid). (Historically, this process could not have been used, as 98% oil of vitrol was not available)
Aqua Ragia/Spirit of turpentine/Oil of turpentine/Gum turpentine - turpentine, formed by the distillation of pine tree resin.
Aqua Regia (Latin: "royal water") - a mixture of aqua fortis and spirit of salt.
Butter (or oil) of antimony - antimony trichloride. Formed by distilling roasted stibnite with corrosive sublimate, or dissolving stibnite in hot concentrated hydrochloric acid and distilling.
Calomel/horn quicksilver/horn mercury - mercury(I) chloride, a very poisonous purgative formed by subliming a mixture of mercuric chloride and metallic mercury, triturated in a mortar and heated in an iron pot. The crust formed on the lid was ground to powder and boiled with water to remove the calomel.
Caustic potash/Caustic Wood Alkali - potassium hydroxide, formed by adding lime to potash.
Turpeth mineral - hydrolysed form of mercury(II) sulfate.
Verdigris - copper(II) carbonate or (more recently) copper(II) acetate. The carbonate is formed by weathering copper. The acetate is formed by vinegar acting on copper. One version was used as a green pigment.
White lead- lead carbonate, a toxic pigment, produced by corroding stacks of lead plates with dilute vinegar beneath a heap of moistened wood shavings. (replaced by blanc fixe & lithopone)
White vitriol - zinc sulfate, formed by lixiviating roasted zinc blende.
Venetian White - formed from equal parts of white lead and barium sulfate.
Zaffre - impure cobalt arsenate, formed after roasting cobalt ore.