Gold is relatively rare and shiny with a color and lustre that is uncommon in other natural materials. Gold has relatively few practical uses aside from prestige goods, which means that it's value is not decreased socially by being used for other things. This makes gold rare and "special". Things that are rare and have few practical uses can be used both as a compact medium of exchange, but also for costly signaling. Not all societies used gold and other precious metals for this purpose, exclusively. Mesoamerica and Ancient China used jade, for instance.

The verifiably oldest extant gold jewelry and artifacts have been found at the Varna Necropolis in Bulgaria, dating to approximately 4500 BCE -- more than six thousand years ago, well before the oldest written records. The Smithsonian Magazine published a good general-interest article "Mystery of the Varna Gold".

Hi OP, there's lots of room for an in depth treatment of this question, but just FYI, you can get started with a few old posts here

• FAQ section Why was gold always considered so valuable?

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