Fracture

Types of fracture are:

Conchoidal (shell like) which results in concentric concave ridges
Subconchoidal, which is similar to conchoidal but less prominant, often lacking the concentric ridges.
Even. A fairly smooth, flat break that may visually resemble a cleavage plane.
Granular. A fine-grained break resembling the surface of a sugar cube.
Spintery. A fibrous break that resemles splintered wood.
Uneven. A general catagory used to describe fractures with an irregualr appearance such as aggregate gem materials like Serpentine.
Steplike. Breaks that may be a combination of cleavages in more than one direction or a combination of cleavages and fractures.