Alchemical symbols were used to denote chemical elements and compounds, as well as alchemical apparatus and processes, until the 18th century. Although notation was partly standardized, style and symbol varied between alchemists. Lüdy-Tenger[1] published an inventory of 3,695 symbols and variants, and that was not exhaustive, omitting for example many of the symbols used by Isaac Newton. This page therefore lists only the most common symbols.
According to Paracelsus (1493–1541), the three primes or tria prima – of which material substances are immediately composed – are:[2]
See main article: Classical elements. Western alchemy makes use of the four classical elements. The symbols used for these are:[3]
The seven metals known since Classical times in Europe were associated with the seven classical planets; this figured heavily in alchemical symbolism. The exact correlation varied over time, and in early centuries bronze or electrum were sometimes found instead of mercury, or copper for Mars instead of iron; however, gold, silver, and lead had always been associated with the Sun, Moon, and Saturn.The associations below are attested from the 7th century and had stabilized by the 15th. They started breaking down with the discovery of antimony, bismuth, and zinc in the 16th century. Alchemists would typically call the metals by their planetary names, e.g. "Saturn" for lead, "Mars" for iron; compounds of tin, iron, and silver continued to be called "jovial", "martial", and "lunar"; or "of Jupiter", "of Mars", and "of the moon", through the 17th century. The tradition remains today with the name of the element mercury, where chemists decided the planetary name was preferable to common names like "quicksilver", and in a few archaic terms such as lunar caustic (silver nitrate) and saturnism (lead poisoning).[4]
The following symbols, among others, have been adopted into Unicode.
The alchemical magnum opus was sometimes expressed as a series of chemical operations. In cases where these numbered twelve, each could be assigned one of the Zodiac signs as a form of cryptography. The following example can be found in Pernety's Dictionnaire mytho-hermétique (1758):[7]
Several symbols indicate units of time.
A list of symbols published in 1931:
An 1888 reproduction of a Venetian list of medieval Greek alchemical symbols from about the year 1100 but circulating since about 300 and attributed to Zosimos of Panopolis. The list starts with for gold and has early conventions that would later change: here ☿ is tin and ♃ electrum; ☾ is silver but ☽ is mercury. Many of the 'symbols' are simply abbreviations of the Greek word or phrase. View the files on Commons for the list of symbols.
See main article: article and Alchemical Symbols (Unicode block). The Alchemical Symbols block was added to Unicode in 2010 as part of Unicode 6.0.[8]
Other symbols commonly used in alchemy and related esoteric traditions: