It's now feasible to begin work to develop a perfect and much less expensive substitute for gold and other precious metals.
The hell, man? The purpose precious metals serve is as a medium of exchange. There is no "substitute" that wouldn't be equally rare and expensive; the fact that they are rare and expensive is what makes them useful media of exchange.
Rare and expensive are synonyms. Gold doesn’t corrode either. That is its main quality as a store of value and the secret to its continuing status.