Alloy is a solid solution made by mixing two more metals or nonmetals and metals. Alloy is usually made by melting and mixing the materials and letting them cool down at a normal temperature. Alloys are prepared in order to give a material certain desired properties.

The alloy often doesn’t share the qualities of its constituents. A good example for that is solder – this alloy is made by tin and lead. However, it has a lower melting point than both of its constituents. This is why this alloy is used for soldering electrical wires.

Few people know that pure gold can’t be used to make jewelry, because it is too soft. In order to make it hard, it is alloyed with silver or copper. This is why the purity of gold is measured in carats. 24 carats means that gold is pure while 18 carats means that it contains 18 parts gold in 24 parts of the alloy’s weight.