Weathering is the breaking down of rock by many natural agents like water, wind, and gravity. There are two types of weathering: Mechanical and Chemical Weathering. Mechanical Weathering is when rocks are broken down WITHOUT a chemical change. They are changing their physical properties. Mechanical weathering can split rocks in half and turn them into dust! Some examples of Mechanical Weathering are ice wedging (when water freezes into ice in cracks of rock and expands the rock cracks) and salt weathering (rock is forced apart by the formation of salt crystals). Chemical Weathering is when rocks are broken down BY changing their chemical properties. That means that the rock are changing into a new compound! Some examples are clay formation (rocks turn into clay which can be broken down) and rusting (Oxygen turns iron red and makes it weaker).