You might find the idea of an alloy as a "mixture of metals" quite confusing. How can you mix together two lumps of solid metal? The traditional way of making alloys was to heat and melt the components to make liquids, mix them together, and then allow them to cool into what's called a solid solution (the solid equivalent of a solution like salt in water). An alternative way of making an alloy is to turn the components into powders, mix them together, and then fuse them with a combination of high pressure and high temperature. This technique is called powder metallurgy. A third method of making alloys is to fire beams of ions (atoms with too few or too many electrons) into the surface layer of a piece of metal. Ion implantation, as this is known, is a very precise way of making an alloy. It's probably best known as a way of making the semiconductors used in electronic circuits and computer chips. (Read more about this in our article on molecular beam epitaxy.)