The entire purpose of this exercise is to recognize that an easily recognized property, like hardness, is an important key to learning how to identify a mineral.
(The entire purpose of this exercise; is; to recognize that an easily recognized property, like hardness, is an important key to learning how to identify a mineral)
The entire purpose of this exercise
is
to recognize that an easily recognized property, like hardness, is an important key to learning how to identify a mineral