I love these nylon coated steel cables that come in a variety of colors. We prefer to cover the metal screw type clasp which gives a more finishing touch to the necklace as well as making it more comfortable to wear around the neck, especially for those with metal allergies.
You can cover the clasp right on the cable as they are generally safe to bake in the oven at the typical clay temperature. The other option is to cut the screw end off the cable (see below) so you can remove the clasp. After covering the clasp with clay (C & D) and replacing it on the cable along with your pendant or beads, a new screw end (A) can be reattached.
(B) Make sure you use heavy duty or memory wire shears to cut the steel cable or you will ruin your good jewelry wire cutters.
(C) Roll a medium thin sheet of clay out and trim to the same width as the screw clasp.
(D) Add and rub in a little liquid clay on the clasp before wrapping in the clay. Make sure the clay fits nice and snug around the clasp so it does not slip after baking. Bake your clasp.
(E) Replace the clay covered clasp onto the cable and then finish the cable end off with a new screw end piece by crimping tightly with pliers.
Just an update as to where to buy these cables. They are available in Black at Shades of Clay (scroll down a bit on the page).