The Sixth Key is about marriage and measure. ‘The male without the female is looked upon as only half a body’, Basil writes, so the opposites of the work must be joined; but everything depends on just measure, like seed in a field: too much and nothing ripens, too little and weeds choke it. Let there be ‘neither too little nor too much’.
What the engraving shows
Basil Valentine’s Sixth Key, from the Musaeum Hermeticum. Photograph: Wellcome Collection, CC BY 4.0; colours added.
The engraving shows a bishop joining the hands of a king and a queen under a rainbow, with the Sun and the Moon in the clouds. On the left a fire-haired figure stands at a furnace with a swan on top; the text’s riddle begins ‘The twofold fiery male must be fed with a snowy swan’. On the right stands an old man with a trident, Neptune, who in the text ‘has prepared his bath’.
What it teaches
The Sixth Key: the marriage. Opposites are joined, and everything depends on measure: too much seed and nothing ripens, too little and weeds take over. Give just measure, “neither too little nor too much”.
The Sixth Key, in full
The male without the female is looked upon as only half a body, nor can the female without the male be regarded as more complete. For neither can bring forth fruit so long as it remains alone. But if the two be conjugally united, there is a perfect body, and their seed is placed in a condition in which it can yield increase. If too much seed be cast into the field, the plants impede each other's growth, and there can be no ripe fruit. But if, on the other hand, too little be sown, weeds spring up and choke it. If a merchant would keep a clear conscience, let him give just measure to his neighbour.
If his measure and weight be not short, he will receive praise from the poor. In too much water you may easily be drowned; too little water, on the other hand, soon evaporates in the heat of the sun. If, then, you would attain the longed-for goal, observe just measure in mixing the liquid substance of the Sages, lest that which is too much overpower that which is too little, and the generation be hindered. For too much rain spoils the fruit, and too much drought stunts its growth. Therefore, when Neptune has prepared his bath, measure out carefully the exact quantity of permanent water needed, and let there be neither too little nor too much.
The twofold fiery male must be fed with a snowy swan, and then they must mutually slay each other and restore each other to life; and the air of the imprisoned fiery male will occupy three of the four quarters of the world, and make up three parts of the imprisoned fiery male, that the death-song of the swans may be distinctly heard; then the swan roasted will become food for the King, and the fiery King will be seized with great love towards the Queen, and will take his fill of delight in embracing her, until they both vanish and coalesce into one body. It is commonly said that two can overpower one, especially if they have sufficient room for putting forth their strength.
Know also that there must come a twofold wind, and a single wind, and that they must furiously blow from the east and from the south. If, when they cease to rage, the air has become water, you may be confident that the spiritual will also be transmuted into a bodily form, and that our number shall prevail through the four seasons in the fourth part of the sky (after the seven planets have exercised power), and that its course will be perfected by the test of fire in the lowest chamber of our palace, when the two shall overpower and consume the third. For this part of our Magistery skill is needed, in order to divide and compound the substances aright, so that the art may result in riches, and the balance may not be falsified by unequal weights. The sky we speak of is the sky of our Art, and there must be justly proportioned parts of our air and earth, our true water and our palpable fire.
Basil Valentine, The Twelve Keys (1599), in the English of the Hermetic Museum (1893).
In Lead to Gold
In Lead to Gold, the Sixth Key’s engraving is the plate of Gate 4, Conjunction, in the Shadow work part of the path. The whole of the Twelve Keys is in the app’s Library, with a note in plain words on every key.
Last updated October 25, 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.
What does Basil Valentine’s Fifth Key mean?: Basil Valentine’s Fifth Key (1599) explained: Venus, Cupid and the lion, the magnet that draws like to like, and the full text of the key in English.
What does Basil Valentine’s Seventh Key mean?: Basil Valentine’s Seventh Key (1599) explained: the circle of Chaos and the four seasons, why the fire must stay gentle, and the full text in English.
What is conjunction in alchemy?: Conjunction, stage 4 of the twelve stages of alchemy: joining your opposites. What the alchemists did, and what it means for you.
What are Basil Valentine’s Twelve Keys?: The Twelve Keys of Basil Valentine (1599): who he was, the twelve engravings, and what each key teaches about the Great Work, in plain words.
