The practice of external Alchemy (waidan) is oldest. The waidan practitioner takes the ingredients seals them in a crucible, fires it and when the process is complete he crapes the elixir off the lid. Taking this powder he makes pills with it.   So in other words the waidan practitioner starts with physical ingredients and ends with a physical elixir. Waidan never exits the physical level. Alchemy therefore as it was originally understood was a physical art. An alchemist would have been very disappointed if his ingredients were transmuted into qi and went up in smoke as there would be nothing for him to gather upon opening the crucible.   Early neidan practitioners were the same, they wanted to make the Jindan. When the Jindan was formed there life was prolonged, sickness was cured and they gained occult powers such as being able to see and communicate with the gods.   The idea of refining jing to qi, qi to shen and shen to tao is a later development and is not even neidan but Taoist yoga.   Neidan (internal elixir) starts with ingredients and ends with the production of the jindan. It is like waidan it starts on the physical level and ends on the physical level, it is alchemy.   Converting jing to qi etc is not neidan or waidan, it is not alchemy but Taoist yoga its goal is not the same.