The rock or sediment associated with a soil's development is referred to as its parent material; it's the starting point for the process of soil formation. During early formation, soils are not so different from their parent materials. With time however, soils will contain less and less features of their original parent material, until eventually taking on an identity all of their own. In order to make an accurate assessment of the amount of soil formation that has occurred, the parent material must be known to establish a base line, or starting point in the soil's formation.