Oooh, I know about this, it goes back to chinese alchemy. Gold was considered to be the key to longevity, but it was supposed to be alchemically altered gold. The belief was that you could infuse natural gold with spiritual potency by combining it with other stuff.
Enter cinnabar - it is a red (i.e. auspciously) colored mineral which, when roasted, produces mercury. This was considered magical. Now, combine it with the fact that mercury can dissolve gold and form an amalgam, and you end up with a long line of very rich ancient Chinese people slowly poisoning themselves.
Alchemy was a philosophical and proto-scientific tradition of trying to create precious metal from common ones.
But I didn't know they fused gold and mercury to create a "super potion", thanks for the history-chemistry lesson. 🤠
That's the aspect of alchemy we're familiar with, but it turns out to only be one branch of Western alchemy, which was heavily influenced by Eastern alchemy (as diffused through the mid-east).
I didn't know much about non-precious metal alchemical traditions until reading up on the history of chemistry in 'Caveman to Chemist', which has a really great set of chapters on it.