Alchemists contributed to science and I read somewhere that a lot of their mysticism or metaphorical language was a result of secrecy. But they operated under a flawed paradigm. Alchemy was big on the idea of using a small portion of something (usually gold) as a seed which would take surrounding matter and transform it into the desired material (usually gold :P). Like a seed turning air, water and soil into a plant because it's a seed and that's the end of that. With enough metaphor behind it, it's true. But it doesn't answer any "why?".

Do you know about the tin pest? If not, it's the type of tin that comes to be from normal tin exposed to low temperatures. It possesses a fascinating property: if you put even a tiny bit of tin pest on a brick of white tin, all of it will slowly turn into the pest form. Also, heat could revert the process. It wasn't insane to think there could be such seeds for other materials.

Alchemy had its time. Reimagining it with modern science isn't likely (or IMO possible), even though all the lingo physicists use could make you think they strive for the same secrecy alchemists wanted. ;)