CLEF III., The Third Key, facing page 65, from <i>Practica, cum duodecim clavibus et ... Les douze clefs de philosophie / de frere Basile Valentin ... : Traictant de la vraye medecine metalique. Plus l'Azoth, ou le moyen de faire l'or caché des philosophes.</i> by Basilius Valentinus (<a href="https://en.wikipedia.org/wiki/Basil_Valentine" class="extiw" title="w:Basil Valentine">Basil Valentine</a>) Paris : P. Moet, 1660.
Basil Valentine in his writings provided twelve “keys,” a widely reproduced sequence of alchemical operations encoded allegorically, both in words and in images. The images were essential to the communication and had to depict the same scene, regardless of the artistry.
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Basil Valentine</div>
1660<div style="display: none;">date QS:P571,+1660-00-00T00:00:00Z/9</div>
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