Separation techniques are based on differences in the physical or chemical properties of the gangue and the ore. These differences may include differences in density, particle size, magnetic properties, or solubility.

Gangue must be removed from the ore before metal extraction to obtain a purer form of the metal and improve the efficiency of the extraction process.

Gangue materials are impurities such as soil, sand, and other unwanted substances present in ores mined from the earth.

Yes, metals such as copper and silver are found in nature as both free elements and in combined states as sulphide or oxide ores.

Many metal ores are oxides because oxygen is a very reactive element and is abundant on Earth. The metal ores form as a result of the reaction between metals and oxygen present in the Earth’s crust.