What does VITRIOL mean in alchemy?

VITRIOL is both a real substance and an alchemical motto. As a substance, vitriol is the old name for crystalline sulphates such as green vitriol (iron sulphate) and blue vitriol (copper sulphate), from which sulphuric acid, ‘oil of vitriol’, was made. As a motto, its letters stand for Visita interiora terrae, rectificando invenies occultum lapidem: ‘Visit the interior of the earth; by rectifying, you will find the hidden stone.’

The motto, word by word

The acronym appears in books printed under Basil Valentine’s name in the early 1600s.

Visita: visit.
Interiora terrae: the inner parts of the earth.
Rectificando: by rectifying, that is, purifying and setting right.
Invenies: you will find.
Occultum lapidem: the hidden stone.

Look within

In Lead to Gold’s list of symbols, VITRIOL is ‘a reminder to look within’. In spiritual alchemy the earth is you: go down into what is heavy and hidden, set it right gently, and the stone, the precious thing, is found there, not somewhere else. What is shadow work?

The substance

Vitriol was one of the most useful materials in the old laboratory. Heated, it gave off the strong acid the alchemists used to dissolve other matter.

In the old masters’ words

“Seek therein, and be not weary; the result justifies the labour.” Basil Valentine, The Twelve Keys, 1599

In Lead to Gold

Vitriol is one of the 116 symbols in Lead to Gold, learned with flashcards.

Last updated October 24, 2026.

Lead to Gold: Shadow Work, on Google Play

The alchemists’ Great Work, made into ten quiet minutes a day: twelve gates, a private journal, and a line of wisdom from the old masters. Free to download, for Android.

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Keep reading

What do the alchemical symbols mean?: The main alchemical symbols and what they mean: the four elements, the three principles, the seven planetary metals, and the signs for the operations.
What is shadow work?: Shadow work means looking honestly at the parts of yourself you hide or judge. Where the idea comes from, Carl Jung and alchemy, and how to begin gently.
What is the philosopher’s stone?: The philosopher’s stone was alchemy’s legendary goal: a substance to turn lead into gold. What the alchemists believed, how it was made, and what it means now.