Copper is not technically the best electrical conductor, or a physical object that allows the transference of heat or electricity through it. Silver is actually considered to be the most effective metal for transferring heat and electricity; however, it tends to be more costly than other metals.
Copper has a conduction performance that is roughly similar to silver, but is typically much cheaper, making it the more commonly used material for electrical wiring. While silver is the best electrical conductor for metals, it is not the overall best conductor – diamonds conduct heat and electricity approximately five times more effectively than silver does.
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