Here's a photo I harvested from an online offering, a few years ago. The beads shown are identified as "coral." This is a very common mistake—even though cameo shell does not really look like coral. Interestingly, with these beads you can see the darker redder ridges that are the external portions of the mollusk shell. Many cameo shell beads retain some of this feature, even if it's only faint reddish stripes in the surface. These particular cylindrical beads are from Nigeria, where this shape is preferred for actual coral beads as well. The cameo shell and coral beads for Nigeria were probably all made at Naples/Torre Del Greco. JDA.