Answer
Cleavage and fracture are both terms used to describe the way a mineral breaks, but they differ in the manner and quality of the break.
Cleavage:
Cleavage refers to the tendency of a mineral to break along planes of weakness, producing smooth, flat surfaces that are parallel to each other. These cleavage planes are determined by the arrangement of atoms or ions within the crystal lattice of the mineral. When a mineral is struck or subjected to stress in a specific direction, it breaks along these planes, creating clean, flat surfaces. The resulting cleavage surfaces often exhibit reflective and smooth textures. Cleavage is described by the number and orientation of the planes on which the mineral readily breaks.
Fracture:
Fracture, on the other hand, describes the way a mineral breaks when it does not exhibit cleavage. When a mineral lacks distinct planes of weakness, it breaks in an irregular or random manner. Fracture surfaces are typically rough, jagged, and uneven, unlike the smooth and flat surfaces of cleavage. Fracture can occur in any direction, and the resulting fragments may have varied shapes and textures. Fracture can be described using terms such as conchoidal (shell-like), uneven, fibrous, or splintery, depending on the appearance of the broken surface.
In summary, cleavage refers to the tendency of a mineral to break along flat and smooth planes of weakness, while fracture describes the irregular and rough manner in which a mineral breaks when it lacks distinct cleavage planes.
Work Step by Step
Cleavage and fracture are both terms used to describe the way a mineral breaks, but they differ in the manner and quality of the break.
Cleavage:
Cleavage refers to the tendency of a mineral to break along planes of weakness, producing smooth, flat surfaces that are parallel to each other. These cleavage planes are determined by the arrangement of atoms or ions within the crystal lattice of the mineral. When a mineral is struck or subjected to stress in a specific direction, it breaks along these planes, creating clean, flat surfaces. The resulting cleavage surfaces often exhibit reflective and smooth textures. Cleavage is described by the number and orientation of the planes on which the mineral readily breaks.
Fracture:
Fracture, on the other hand, describes the way a mineral breaks when it does not exhibit cleavage. When a mineral lacks distinct planes of weakness, it breaks in an irregular or random manner. Fracture surfaces are typically rough, jagged, and uneven, unlike the smooth and flat surfaces of cleavage. Fracture can occur in any direction, and the resulting fragments may have varied shapes and textures. Fracture can be described using terms such as conchoidal (shell-like), uneven, fibrous, or splintery, depending on the appearance of the broken surface.
In summary, cleavage refers to the tendency of a mineral to break along flat and smooth planes of weakness, while fracture describes the irregular and rough manner in which a mineral breaks when it lacks distinct cleavage planes.
