Copper Pans

Copper conducts heat more efficiently than any other metal, which is why it has always been popular in professional kitchens. Old unlined pans can be harmful, as copper ions leach into foods during cooking and the human body can only get rid of so many before they build up to toxic levels in the liver, causing damage. Old copper pans are lovely things anyway and are good in the kitchen purely for their decorative effect. Modern copper pans are lined with tin, which creates reasonably efficient cookware, though its relatively low melting point means you have to take care not to expose it to high heat for too long. If left empty on a high flame the cooking surface is ruined and no amount of oiling and seasoning will bring it back.