(Trading symbol HG) An industrial metal traded as a commodity on both the spot and the futures markets. On COMEX, a contract unit of copper equals 25,000 pounds. contract prices for copper move in minimum increments of $.0005, or $.05, per pound which means that a $.01 move in the price equals $250 per contract. There are exceptions, but the exchange will call a halt to trading if the price on copper fluctuates more than $.20 per pound ($5000 per contract) above or below from the previous day's closes. See minimum price movement.