From
A Dictionary of Symbols by
Juan Eduardo Cirlot (translated by Jack Sage):
In astrology they are called ‘terrestrial’ or ‘subterranean planets’, because of the analogous correspondences between the planets and the metals. For this reason astrologers consider that there are only seven metals (influenced by the same number of spheres), which does not mean that mankind during the astrobiological period did not recognize more. As Piobb has pointed out, some engineers have noted that the seven planetary metals make up a series which is applicable to the system of the twelve polygons. But, apart from the theory of correspondences, the metals symbolize cosmic energy in solidified form and, in consequence, the libido. On this basis, Jung has asserted that the base metals are the desires and the lusts of the flesh. Extracting the quintessence from these metals, or transmuting them into higher metals, is equivalent to setting creative energy free from the fetters of the sense world, a process identical with what esoteric tradition and astrology regard as liberation from the ‘planetary influences’. The metals can be grouped within a progressive ‘series’ in which each metal displays its hierarchical superiority over the one preceding it, with gold as the culminating point of the progression. This is why, in certain rites, the neophyte is required to divest himself of his ‘metals’ — coins, keys, trinkets — because they are symbolic of his habits, prejudices and characteristics, etc. We, for our part, however, are inclined to believe that in each particular pairing of planet with metal (as Mars with iron) there is an essential element of the ambitendent, in that its positive quality tends one way and its negative defect tends the other. Molten metal is an alchemic symbol expressing the coniunctio oppositorum (the conjunction of fire and water), related to mercury, Mercury and Plato’s primordial, androgynous being. And at the same time, the solid or ‘closed’ properties of matter emphasize its symbolism as a liberator — hence the connexion with Hermes the psychopomp <...> . The correspondences between the planets and the metals, from inferior to superior, are: Saturn — lead, Jupiter — tin, Mars — iron, Venus — copper, Mercury — mercury, Moon — silver, Sun — gold.
