What does the term 'cleavage' specifically refer to in minerals?

The term 'cleavage' in the context of minerals refers specifically to the characteristic of minerals to break along specific planes of weakness, resulting in smooth surfaces. This property is a result of the arrangement of atoms within the mineral's structure, which leads to predictable breakage along certain crystallographic directions. Each mineral exhibits cleavage in unique patterns determined by its internal structure and bonding.

This distinction is essential in mineral identification, as the presence and quality of cleavage can vary significantly between different minerals. For example, minerals like mica display perfect cleavage, allowing them to be easily separated into thin sheets, while others may show cleavage in only one direction or not at all.

The other options, while relevant to mineral properties, do not correctly define 'cleavage.' The structure of crystal faces relates to the external manifestation of a mineral's internal symmetry but does not speak to how a mineral breaks. The ability to bend without breaking describes ductility, which is a different mechanical property. Surface texture pertains to the external characteristics of a mineral's surface rather than its breaking pattern.