Gold is a collectible, with a marginal use as a commodity. A commodity is an input to industrial processes, not really an asset though you can call commodities assets too if you want to.
It used to be a currency quite a while ago - people would actually use it in contracts, most importantly long term debt contracts (long term contracts is where the value/acceptance of the currency really shows; imagine taking or issuing a 30yr mortgage in Bitcoin, as in the homeowner is obliged to pay fixed X Bitcoin per month, lol). A big part of the great depression fighting/relief was to make debt contracts denominated in gold unenforceable.
It used to be a currency quite a while ago - people would actually use it in contracts, most importantly long term debt contracts (long term contracts is where the value/acceptance of the currency really shows; imagine taking or issuing a 30yr mortgage in Bitcoin, as in the homeowner is obliged to pay fixed X Bitcoin per month, lol). A big part of the great depression fighting/relief was to make debt contracts denominated in gold unenforceable.