Paracelsus
By the mediation of Vulcan, or fire, any metal can be generated from Mercury. At the same time, Mercury is imperfect as a metal; it is semi-generated and wanting in coagulation, which is the end of all metals.
Up to the halfway point of their generation, all metals are Mercury. Gold, for example, is Mercury; but it loses the Mercurial nature by coagulation, and although the properties of Mercury are present in it, they are dead, for their vitality is destroyed by coagulation." [Paracelsus, De Morbis Metallicis, Lib. III., Tract II]
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