Magnetism is ideal for separating mixtures of two solids, with one part having magnetic properties. Some metals like iron, nickel, and cobalt have magnetic properties whiles gold, silver and aluminum do not. Magnetic elements are attracted to a magnet.

It works like this: Let us take a mixture of sand and iron filing for example.

To separate this, spread out the mixture on a flat surface. Run a magnet bar over the surface. You will notice that the magnetic elements (iron filings) will be attracted to the magnet over it. After a number of runs, all the sand will be free from any iron filing.