yes, mercury or ``prima materia'' is alchemy code for sperm as they are looking for the beginnings of the material, or philosopher's stone.

Common Mercury is silvery and opaque, (Ummmm good, huh?) that of the philosophers is clear at first, :as clear as the tears of the eye" (Bernard Trevisan, etc.), but when its salt is dissolved in it, it is milky and opaque. "The Clear and Diaphanous Menstruum, Philosophical Vinegar is by reason of the Spirit of Philosophical Wine Diaphanous, not of a Milky Colour, but in the distillation of a Menstruum it is made Milky, because the Acidity of the said Vinegar is debilitated by the Aridity of the Body dissolved (in it)." Secrets of the Adepts". Weidenfeld. Common mercury only becomes clear and transparent by being dissolved in an acid. The two things are exactly opposite.
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