The crossword solution for the term CONTAINING COPPER is CENT, which is a four-letter word. CENT is a unit of currency in many countries, including the United States. It is also used to refer to coins made of copper or bronze, which are often used as a form of payment. Copper is a metal that has been used for centuries in coins and other forms of currency. It is also used in many other applications, such as electrical wiring and plumbing.