Physical state: All metals are solids at room temperature except mercury and gallium.
Lustre: Metals possess a high lustre (called metallic lustre).
Hardness: Most of the metals are hard and strong.
Melting point & Boiling point: Usually metals possess high melting and boiling points are vaporize only at high temperatures.
Density: Metals have a high density.
Ductility: Metals are usually ductile. In other words, they can be drawn into thin wires without breaking.
Malleability: Metals are usually malleable. They can be beaten into thin sheets without cracking.
Conduction of heat & electricity: Metals are good conductors of heat and electricity. Silver and copper except in this property.
Solubility: Usually metals do not dissolve in liquid solvents.

This method is employed when the ore is in a very pure form. The ore is treated with a suitable reagent such that the ore is soluble in it but the impurities are not. The impurities are removed by filtration. The solution of the ore, i.e., the filtrate is treated with a suitable reagent which precipitates the ore.
eg: Bauxite Al₂O₃.2H₂O is the ore of Aluminium.

Principle: This process depend on the preferential wettability of the ore with oil (pine oil) and the gangue particles by water. Lighter ores such as sulphide ores are concentrated by this method. Eg. Zinc blende (ZnS).

Method: The reused ore is taken in a large tank containing oil and water and agitated with a current of compressed air. The ore is wetted by the oil and gets separated from the gangue in the form of froth. Since the ore is lighter, it comes on the surface with the froth and the impurities are left behind. eg: Zinc blende.

Principle: The magnetic properties of the ores form the basis of separation. When either the ore or the gangue is magnetic, this method is employed. e.g., Tinstone SnO₂, the ore of tin.

Method: The crushed ore is placed over a conveyer belt which rotates around two metal wheels, one of which is magnetic. The magnetic particles are attracted to the magnetic wheel and fall separately apart from the non-magnetic particles.

Principle: The difference in the densities or specific gravities of the ore and the gangue is the main principle behind this method. Oxide ores are purified by this method. Eg. Hematite Fe₂O₃ ore of iron

Method: The ore is poured over a sloping, vibrating corrugated table with grooves and a jet of water is allowed to flow over it. The denser ore particles settle down in the grooves and lighter gangue particles are washed down by water.