cleavage planes

Cleavage planes are specific directions within a mineral where it tends to break more easily, resulting in smooth, flat surfaces. Think of them as natural lines of weakness created by the mineral's internal structure, where bonds between atoms are weaker. When a mineral is split along these planes, it produces predictable and consistent shapes. These features help geologists identify minerals and understand their internal arrangement. Cleavage planes are important because they reveal how the mineral is built and how it might break or fracture naturally.