No no it wasn’t just a shiny metal. Silver and gold were (still are) noble metals, and that means they are more inert than other metals, and by inert I mean “it doesn’t rust or tarnish”. Silver sometimes tarnishes, but gold is very hard to tarnish.

And you may think, so what, big deal, it just saves time polishing metal. Right? No, if you ever ate from a brass or any other alloy metal cutlery/plates, you will remember the absolutely horrible bitter taste these metals have. You pretty much have to hard scrub and polish each piece daily to avoid getting that taste. Tarnished silver otoh, doesn’t taste as bad. So not only it takes longer to tarnish but even if it does it gets a pass. Bear in mind stainless steel and plastic weren’t really a thing back then, so you’d be stuck with metal or wood for cutlery.

But wait, there is more. Both silver and gold are particularly malleable and ductile; this means you can hammer them, beat them, bend them, and spin them into very thin threads and the metal won’t break as easily as other metals do. I’ve worked as a silversmith so I’ve experienced this first hand. Working brass into shape and adding ornamentation to it is very hard, you need to anneal it constantly and use more force. It cracks more easily while you work it too. Copper is slightly better, but silver is way ahead any of them, and gold is just like working butter. There is no comparison. Much easier, really good results. Also gold has a slightly higher melting point than silver, meaning it’s somewhat easier to solder.

All this makes gold and silver the only fitting choices for fine jewelry and luxury items such as silverware, trophies, embroidered clothing, etc. And these items signify wealth and status, so, obviously, this made gold and silver very valuable and useful back in the day.