The answer to this question depends very much on what you want to do and how much money you want to spend to do it. There are a number of things that make good conductors of electricity.
Copper is so far the most used electricity conductor, it does a great job and it’s the best value. It is not as expensive as silver or gold. However copper oxidizes and tarnishes badly if it is exposed to air or water and it also very easily “pits”, meaning it burns away leaving holes and dips. If any sparks or electric arcs are caused to form on its surface that means that the copper is no good for use to make contacts for electrical switches.
Silver is perhaps the best conductor of electricity, but it is expensive and oxidizes and tarnishes if exposed to air or water. It pits if any sparks or electric arcs are caused to form on its surface. So, like copper, pure silver is no good for use to make contacts for electrical switches. However silver can be used to make very good contacts in electrical connectors, if it is alloyed with other metals, good switch contacts.
Gold is the best conductor of both heat and electricity.
It is not affected by air and most reagents. Heat, moisture, oxygen, and most harsh agents have very little chemical effect on gold, making it well suited for use in coins and jewelry.
Its main benefit of using gold is that it does not oxidize or tarnish if exposed to air or water. So, it is often used to make the contacts in electrical connectors and, if it is alloyed with other metals, good contacts in electrical switches. It’s also very soft and easy to bond to other materials.
Gold is often more flexible metal or metal alloys to make contacts in electrical connectors and switches. Because it can be made into extremely thin wires which don’t break easily and have very low resistance to the flow of electric current. It is also used to make the links between the connection pads on the chips inside integrated circuit modules and their external connecting pins.
The main disadvantage of using gold either for wires or for switch contacts is that it is very expensive that’s why we replace it with copper or silver.