Ⅰ. TO EXPLANATE THE FOLLOWING TERMS ( Ten terms , 2 marks per term, total 20 marks) 1. Ore: the rock material or minerals which are mined for a profit; Gangue Minerals: the minerals having no commercial value, they just happen to be mixed up with the ore minerals;Non-ferrous metal (Base metal): Copper, lead, Zinc, Nickel, Tungsten, Tin, Molybdenum, Bismuth, Stibium