Neriage, Nerikomi, Clay Murrini; they all are similar techniques where clay is coloured with stains or oxides and then cut and re-cut into patterns and then either compressed together to form a single piece with the pattern on both sides, or the clay is laminated onto a clay backing so that it is like a veneer surface. This is then compressed and formed into shape, or as in my little expresso mugs, turned on the wheel. The Japanese have many examples of this as do Venetian bead makers. If you want to follow an expert, then look up Dorothy Fiebleman who produces stunning work.