Minerals should be in their crystal form. The crystal form of a mineral is determined by the arrangement of atoms, ions,or molecules. Different minerals have different crystal structures because their atoms, molecules, or ions are not arranged in the same way. The crystal structure of a mineral affects they way that particular mineral breaks.
This is an example of what a crystal structure looks like. This is the crystal structure of the mineral fluorite.
This is an image of what some minerals may look like in their crystal form.