A gold rush makes sense. But a copper rush? Not so much. And yet, perhaps there is more to gold than aesthetics.
If the conductivity of copper were ten times less, wires would have to be ten times the cross-sectional area to provide the same conductivity.
It is very doubtful that any beings in the universe could develop a civilization remotely comparable with our own without the use of metals.
The importance of metals, particularly iron, and the importance of the discovery of metallurgy can hardly be exaggerated.
The ability to tame fire led to the invention of the art of cooking, and much more.