Granite is a commonly stone used in construction and is often mistaken for marble. Granite is made up of crystal and was heated much as lava is.Granite is heavy like marble, but much harder. It is 7 on the Mohs hardness scale. Unlike marble, it cannot be scratched by a steel knife. Unlike marble, granite doesn’t react to vinegar, lemon juice or other acids. Granite generally has a more sparkly, granular pattern, as opposed to the fluid lines of marble.