This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
Among the metals, only silver conducts electricity and heat better than copper does. That single fact, second place in a field of one competitor, is worth more to the modern world than almost any other property any element on this atlas carries, because it decides what wraps every wire in every building, motor and power line on the planet.
Silver's conductivity edge over copper is real but small, on the order of a few percent, roughly seven percent by most measurements, and silver's market price runs many times higher than copper's, by some estimates around fifty times as much per unit weight, so almost no electrical application actually uses it: the cost of the marginal conductivity gain is nowhere near worth paying at any scale beyond specialized instruments and certain high frequency electronics. Copper delivers nearly silver's performance at a small fraction of the price, and it is far more abundant and far easier to draw into the long, thin, ductile wires an electrical grid needs, which is why copper rather than silver became, and remains, the default conductor of the electrified world.
Copper's chemistry supports the same role from another angle. It does not react with water, so copper wiring buried or exposed to damp conditions does not corrode in the way iron does. That combination, conductivity close to the best available, cost and workability far better than the one metal that beats it, and a stability that keeps installed wiring reliable for decades, is why the choice was never close outside a few specialist niches: copper did not win by being the best conductor. It won by being the best conductor anyone could actually afford to wire a planet with.