Are all metals pure elements

All metals are pure elements, however do not occur in nature necessarily as "pure." Pure being defined as the singular element without added compounds for its stability. For example, Fe2+ (iron) is commonly found in nature as FeO2 (iron oxide) because iron is oxidized in the presence of air (hence the oxygen).

There are a variety of elements that all need some kind of an ion (charged particle) as a supplement for the elements' stability, commonly Lithium, Sodium, Calcium and others are in complex with the "pure" element. Another common example is table salt (NaCl). Sodium metal (Na) is highly reactive with water and humidity and is also often complexed with some other element to maintain stability.