Minerals can be classified based on cleavage or fracture. These two properties refer to the way in which a mineral tends to break. Cleavage is an orderly breakage in well-defined planes. It means that the broken
piece of mineral will have flat and smooth sides. Fracture is a random breakage. If a mineral breaks with
rough, random, uneven surfaces, it is said to have fractured. Because each of your mineral samples have
already been broken from another, larger piece of a mineral, you should be able to tell if it has cleavage or
fractures by looking at its sides. Of your 10 minerals, identify three that experienced cleavage.
Cleavage
Fracture