Metal Utensils: Copper

A heavy metal which conducts heat extremely well, making it ideal for cooking vessels. It is covered by a layer of brownish oxide—pure copper is salmon pink, but the colour of a freshly cut surface darkens in minutes. All copper compounds are poisonous; some of them, though not the oxide, dissolve in water and so are particularly dangerous. Most copper pans are coated inside with tin, and the coating should be renewed as soon as it begins to wear off. Untinned copper is traditionally used in ‘preserving pans’ for making jam, which should be well scoured before use. There have been cases of poisoning from unlined copper vessels, especially when vinegar or other liquids containing acetic acid have been allowed to stand in them, forming copper acetate.