Alchemy is certainly possible with today's technology, and has been done: https://en.wikipedia.org/wiki/Synthesis_of_precious_metals https://en.wikipedia.org/w

Alchemy is certainly possible with today's technology, and has been done: https://en.wikipedia.org/wiki/Synthesis_of_precious_metals https://en.wikipedia.org/wiki/Synthesis_of_precious_metals It's not cost effective, but it is cheaper than space colonization.