Why isn't granite used to make automobile engines?
If steel (a metal) is hard and granite ( a nonmetal) is hard, why don't we make automobile engines out of granite?
Some quick answers would be very much appreciated!
Stone is hard (resistant to surface denting) but brittle- difficult to form- and conducts heat poorly. It is also dense- heavy. It is only strong in compression-- in tension it cracks easily.
Metals overcome all these objections.
