Brewing potions in a Copper Cauldron reduces the time you need to wait for certain potions to finish brewing. It does not, however, become hotter faster than the Pewter Cauldron or Brass Cauldron, so it takes the same time to heat the mixture in your Copper Cauldron up to the correct temperature as the other cauldrons. A Copper Cauldron can be bought from Potage's Cauldron Shop for 25 Galleons.