It is important to understand that the point of alchemy is not "turning iron into gold," or in general any other mundane goal. Certainly there is the philosophy of alchemy and the applied science, but even the applied science is not wholly aimed at any specific operation. Alchemical thought is related to Neo-Platonic thought. If there is one central concept in Alchemy it is that the physical reality of our universe mirrors the spiritual reality of our universe.
The Alchemist endeavours, through a series of procedures, to produce the "Great Work" or Philosopher's Stone. What is the Philosopher's Stone? It is a physical substance of ultimate purity. It is the basic perfect solid, of which all other solids are impure corruptions. At the same time, the soul of the Alchemist is refined and purged of purity - thus the one process is the mirror and visible symbol of the other.
It is true that the obvious implication of the process is that base metals can be "transmuted" or "purified" into higher metals. The Alchemical view of the universe predates the periodic table - to the Alchemist, Iron is not a separate metal, but the same universal substance as Gold, only with greater impurity. Silver and Gold are held to be the highest, purest, of elements. It is a logical extrapolation that Silver and gold can be produced by "transmuting" base metals - the process of transmutation in minerals is assumed to be the equivalent of the process of fermentation in the vegetable kingdom.
Certainly there is a great deal of miscellaneous chemical lore caught up in Alchemy, and the "Great Work" is no more the only aim of the Alchemist than the "Knowledge and Conversation of the Holy Guardian Angel" is the only aim of the Ritualist.
Common themes in Alchemy were the creation of the Elixir of Life, which would prolong human life indefinitely, and the creation of artificial life, or homonculi. Both of these practices survived into the Victorian era, and the entire Rosicrucian myth - which begins with the concept of several hundred year old magi, assumes the existence of the Elixir of Life.
But to simply mix the ingredients in Alchemy was pointless. Unless the temperament of the Alchemist was in harmony with the result, the operation would not be successful. (Vialarp)