There are four degrees or types of relief: low relief ( 1/2” in depth) Bas relief, ( 1/2”-2” in depth) and deep relief ( usually over 2” in depth) . In high relief, the forms stand far out from the background. In low relief (best known as bas-relief), they are shallow. In sunken relief, also called hollow or intaglio; the backgrounds are not cut back and the points in highest relief are level with the original surface of the material being carved.