Crystal forms refer to the external shape and structure of a crystal, which is determined by its internal arrangement of atoms. These forms can vary widely, resulting in different geometric shapes such as cubes, hexagons, and prisms. The specific arrangement of atoms within the crystal lattice influences how the crystal grows and its overall appearance. Different minerals exhibit unique crystal forms, which can be classified into categories like isometric, hexagonal, and orthorhombic. The study of crystal forms is essential in fields such as mineralogy and geology, as it helps scientists identify and understand the properties of various minerals and their applications.