Before revision: 300x300px|From left to right: three alloys (beryllium copper, Inconel, steel) and three pure metals (titanium, aluminum, magnesium) An alloy is a mixture of chemical elements of which at least one is a metal .
After revision: 300x300px|From left to right: three alloys (beryllium copper, Inconel, steel) and three pure metalmetallic element, although it is also sometimes used for mixtures of elementsin most casess (titanium, aluminum, magnesium) An alloy is a mixture of chemical elements of which at least one is a metal .