Final answer:
Cast iron is an example of a brittle metal, as opposed to metals like aluminum and copper, which are malleable and ductile.
Step-by-step explanation:
An example of a brittle metal is cast iron. While most metals such as aluminum, mild steel, and copper are generally malleable and ductile due to the way their atoms are arranged and the presence of free electrons that help prevent the cations from coming into contact, cast iron, which contains a higher amount of carbon, tends to be brittle. Brittle materials are more likely to break or shatter when subject to stress rather than bending or deforming as malleable and ductile metals do.