I used to do a lot of wood carving, chip carving in particular. This is a style of woodcarving found in traditional folk art around the world.  Geometric patterns composed of 2, 3, or 4 sided pyramid shaped chips are carved out of the surface, usually with a single knife.  Each chip comes out as a single piece. It can be used to decorate large building surfaces as well as more intricate pieces such as boxes or art frames.