When was solder made?
The first solder was made and used sometime before 4000 BC.
A Conductor, SOLDER IS NOT AN INSULATOR. The most common types of solder are made of tin and lead. Another type is silver solder. All of the materials used are metals and are good conductors of both heat and electricity. If you solder something you would notice if you ever held a wire (without protection) while applying solder to it your finger would probably receive a burn (speaking from experience).