Bezel Setting Gemstone Cabochons Post Firing With Silver Metal Clay
Here are several types of settings for gemstone cabochons that will be set after firing the metal clay.
Fine silver bezel wire. Wrap a strip of fine silver bezel wire around the base of a cabochon. Test fit and adjust the bezel over your cabochon on a flat surface. There shouldn’t be any gaps but the stone should slide in and out of the bezel easily. When you have a good fit, mark the spot where the wire overlaps. Cut it flush (err on the side of too long vs. too short) and file the ends, if necessary, to create a tight seam when the ends are butted together. Check the fit again before sealing.
Method 1: Embed the bezel into the clay and seal the joint neatly with paste clay. (Keep most of the paste on the outside of the joint so you don’t change the fit of the bezel.) Let the clay dry, fill any gaps, dry and fire.
Method 2: Seal the joint of the bezel with paste clay or, better yet, Art Clay Oil Paste. When dry, fire the bezel separately, file the seam smooth and embed in “raw” clay as above.
Tips:
1) The bezel wire must be wide enough to hold the stone in place securely after burnishing, plus 1mm to embed in the clay.
2) Scuff/sand the area of the bezel that will come in contact with the metal clay to give it some “tooth.”
3) With a fine-tipped marker, draw a guide line scant 1mm away from the lower edge of the bezel wire to help you embed the bezel in the clay to an even depth.
Paper-type or sheet metal clay bezels for cabochons. Beautiful custom bezels can be created with paper-type (sheet) metal clay to accommodate cabochons of any size and shape. This technique was pioneered by metal clay artist Jennifer Kahn. Her excellent chapter in the superb book “PMC Technic” (see “Books About Setting Gemstones In Metal Clay,” below) explains in detail how to size the bezel setting so that it fits correctly after firing and offers some variations.
Embedded silver bezel cup settings for calibrated cabochons. For calibrated cabochon stones, you can embed either 1) fine silver bezel cups or 2) sterling silver bezel cups that have been “depletion gilded” (heated and pickled repeatedly to bring the oxides to the surface and remove them, leaving a layer of fine silver on the surface). The settings must be embedded securely into the clay in such a way that the clay can shrink-lock them into place. For depletion gilding sterling silver findings, you can use a traditional pickling product like Sparex, or Silver-Prep from Cool Tools which is supposed to be safer.
