The main element in steel is usually iron. It also contains small amounts of other substances, to improve its properties. Often it contains some carbon (not a metal), and sometimes smaller amounts of other metals.
Hfet
contains enzymes and other substances
Chlorophyll contains the metal magnesium.
metal
A metallic mineral, which contains sufficient quantities of the metal, so that the metal can be extracted efficiently, is called an ore. However, ores can also refer to minerals from which non-metallic substances can be extracted.
substances
metal
Since aluminum is a chemical element it contains no other substances.
Co2
oxygen
Substances made up of two or more different molecules are called compounds. An Ionic compound is made up of a non metal and a metal while a covalent compound is made up of a non metal and another non metal. There is no such thing as a compound composed of a metal and a metal.