Alchemy is an art and Vulcan (the governor of fire) is the artist in it: 'He who is Vulcan has the power of the art ... All things have been created in an unfinished state, nothing is finished, but Vulcan must bring all things to their completion. Everything is at first created in its ''prima materia'', its original stuff; whereupon Vulcan comes, and develops it into its final substance ... God created iron but not that which is to be made of it. He enjoined fire, and Vulcan, who is the lord of fire, was to do the rest ... From this it follows that iron must be cleansed of its dross before it can be forged. This process is alchemy; its founder is the smith Vulcan. What is accomplished by fire is alchemy-whether in the furnace or in the kitchen stove. And he who governs fire is Vulcan, even if he be a cook or a man who tends the stove''.〔Jolande Jacobi ed. ''Paracelsus Selected Writings'', 1951, Princeton〕

Nothing has been created as ''ultima materia'' — in its final state. Everything is at first created in its ''prima materia'', its original stuff; whereupon Vulcan comes, and by the art of alchemy develops it into its final substance.
:Alchemy is a necessary, indispensable art ... It is an art, and Vulcan is its artist. He who is a Vulcan has mastered this art; he who is not a Vulcan can make no headway in it.