IDK if that’s what u menat, but as RobJF one way is create a a gold-pegged stablecoin.
ETH network has a few of them, and there were some ICOs for creating more. Though, gold-pegged stablecoins have little demand and some failed to be created.
It seems most cryptocurrency users don’t care enough on investing in gold, or protecting their investment on gold. Also, storing (real) gold is very expensive, so that makes gold-pegged stablecoins charge higher fee than USD-pegged competitors.
Lastly, I don’t get why nowadays u’d wanna use gold for making payments. fiat or volatile cryptocurrencies are just good enough for that. In fact, one of cryptocurrencies issues is precisely their volatility, which we try to avoid using fiat-pegged stablecoins.
Regarding Cardano itself, we’re still waiting for smart contract and token support on it. As long as they aren’t supported, we can’t have stablecoin tokens as we have on Waves and ETH in example.