Question: What formula did medieval chemists believe could unlock immortality?

Answer: Gold chloride

For thousands of years, humans have been interested in the potential therapeutic benefits of consuming gold. In 2500 BCE, it was common in China to consume gold in the hopes of prolonging life, as gold’s ability to resist corrosion was believed to similarly help the body resist aging.1

More than 2000 years later in approximately 100 CE, the alchemist Wei Boyang continued to promote this belief, explaining, “Gold is the most valuable thing in the world because it is immortal and never gets rotten. Alchemists eat it, and they enjoy longevity.”1

In the medieval period in Europe, attention turned to the potential properties of gold if it was developed into a drinkable form. The rise of alchemy as a field during this time also accelerated interest in the search for an elixir of life. Drinkable gold was thought to be one potential avenue, with alchemists hoping its creation could lead to a formula for immortality.1

In approximately 700 CE, the Iranian chemist Abu Musa Jabir Ibn Hayyan Al-Azdi, who has been credited as the father of Arab chemistry and one of the founders of modern pharmacy (who was also, in written texts, referred to by Europeans as Geber), discovered how to make gold dissolve in liquid in a concoction that became referred to as aqua regia, or royal water.2

The formula Al-Azdi developed was a mixture of nitric and hydrochloric acid that could dissolve pure gold and produce gold chloride. The gold chloride could then be mixed with water to create a drinkable form of gold.1

Chemists were overjoyed at the news of the liquid gold, believing to have unlocked the formula for the elixir of life. Instead, what they had developed was both highly toxic and incredibly corrosive.1

However, enthusiasm for this formula did not wane over the centuries. In the fifteenth century, Paracelsus, a Swiss physician who has been credited as the founder of both modern toxicology and medicinal chemistry, lauded gold chloride as being the perfect element, explaining that consuming the drink could make the body indestructible.3 He wrote, “Drinkable gold will cure all illnesses, it renews and restores.”1

He also noted specifically that the formula could be used to treat mania, epilepsy, and St. Vitus Dance Disease, which was a movement disorder that arose from rheumatic fever. He noted that an added benefit was also that it “made one’s heart happy.”1

In the seventeenth century, the physician Nicholas Culpeper developed gold chloride into a pill that could be dropped in water to treat epilepsy and mental illness. He coated the gold chloride pill in additional gold, for added effect.1

Although the drinkable gold formula may not have been able to treat any of the illnesses it was proclaimed to benefit, it did provide the drinker of the elixir with some lasting effects: kidney damage. Some other short-term effects of the elixir also included profuse salivation, chronic urination, increased sweating, and auric fever, a type of fever that translates roughly as gold fever.1

REFERENCES
  1. Kang L, Pedersen N. Quackery: A Brief History of the Worst Ways to Cure Everything. New York, NY: Workman Publishing; 2017. 
  2. Amr SS, Tbakhi A. Jabir ibn Hayyan. Annals of Saudi Medicine. 2007;27(1):52–53. doi: 10.5144/0256-4947.2007.53.
  3. Borzelleca JF. Paracelsus: Herald of Modern Toxicology. Toxicological Sciences. 200;53(1):2–4. doi: 10.1093/toxsci/53.1.2.