The extensive use of copper for the manufacture of distilling equipment is not a decision made on economic grounds. As of April 2016, copper trades at around $2.22/lb, while 304 stainless steel trades at just $0.89/lb. So it is pertinent to consider: What makes copper as a material of construction so advantageous that it outweighs the higher cost?

Well, copper has been in use since prehistory (the use of copper metal probably begins before 8000 BCE), not least because it is easily released from its common ores, and indeed can even be found as the free metal in nature.