* Fracture patterns: Rocks break along planes of weakness called fractures. These fractures can be straight, curved, or jagged, depending on the rock type and the forces acting on it.
* Rock type: Different rocks have different fracture properties. Some rocks break cleanly, while others break in a more irregular fashion.
* Force of breakage: The force that causes the rock to break can also influence the shape of the newly formed piece. A sudden impact will likely result in a more jagged shape than a gradual weathering process.
In short, the shape of a newly broken rock is a reflection of the rock's internal structure, the forces that caused it to break, and the specific way the rock fractured. It's very difficult to predict what the shape will be beforehand.
