graphite is a basal cleavage
Quartz does not have cleavage. However, it does have fracture. Its fracture is conchoidal.
it probably break apart with cleavage, because the carbon atoms in graphite from sheets that could split apart easily in layers.
it has no cleavage
it has no cleavage
cleavage
Fracture
Hematite has a characteristic fracture, meaning it breaks irregularly with rough or jagged edges and no smooth cleavage planes.
the cleavage is Poor
Sapphire has a mixture of both cleavage and fracture characteristics. It has poor cleavage in one direction and conchoidal fracture, which means it breaks with smooth, curved surfaces similar to glass.
It has both: uneven fracture, and perfect cleavage in three directions.
It has both cleavage and fracture.
Cleavage