This is a technique called "Cutting Edge" by Dan Cormier. He doesn't have a web site that I could find, but he gives a lot of classes, and has published some instructions in the Polymer Cafe magazine. The beads are made with a silver (or alternatively gold) clay mixed with a color clay. Those tiny little silver mica particles reflect light differently from different angles, which is what makes the beads interesting. (Carissa Nichols gives a pretty good explanation on mica shift here.) Also the lines are sort of under the surface, and all the beads are polished to a fine silky smooth finish.
This is a crazy curly-swirly bead that I made with the left over clay from the cutting-edge-beads:
