15+ Stone-Setting Tips for Metal Clay Jewelry Making
You can set gemstones in metal clay — some stones. Some are better candidates for stone setting than others, and different materials and cuts may require different techniques. But one characteristic of metal clay is what makes most of these techniques work: shrinkage. Metal clay shrinks during firing, and that shrinkage is what locks a stone in place.
ABOVE: Arlene Mornick’s sampler metal clay stone-setting bracelet demonstrates many kinds of stones in many kinds of settings. Photo: Jim Lawson
Here are some of the important things you should know as you decide which stone to use and how to set it.
The high temperature at which metal clay must be fired will limit the use of many stones that are sensitive to heat causing them to melt, shatter, or change color during the process. Here are some things to consider:
- Many naturally formed stones have inclusions or flaws that can be exaggerated during heating.
- Synthetics are gems created in a laboratory that are chemically, physically, and optically identical to their counterparts found in nature. Labs often use significant heat to create these stones; many are suitable for metal clay projects.
- Not all manmade stones have a natural counterpart. Cubic Zirconia, or CZ, an economic competitor for diamonds, is a manmade, hard, colorless material made from zirconium dioxide. Clear forms of CZ are generally safe bets, but CZs also come in colors attributable to a variety of oxides. When reheated during a metal clay firing, many such CZs change color.
- Simulated gemstones are created to look like natural stones but do not have the same properties as those stones. They may be many different things, but generally these do not stand up to the heat.
Gemstones with good transparency are commonly faceted into geometric shapes with flat faces that reflect and refract light, giving them a lively appearance. Most faceted stones have a profile like the drawing here, and each of the basic parts plays a role in how a gem is set in metal clay.
- Crown The upper part of the stone, above the girdle.
- Table The large facet at the very top part of the stone. The table should be parallel to the surface of the clay. In a side view, the table will be level with the surface of the clay.
- Girdle Created by a series of thin facets, this girdle marks the widest part of the stone, usually about 2⁄3 of the way up. If the girdle is captured below the clay surface, the stone will stay in place.
- Pavilion The lower part of the stone, below the girdle.
- Culet The bottom of the stone where the pavilion facets meet, usually a very small facet itself rather than a point. This part of the stone needs space to sit properly in the clay. During firing, the clay will shrink anywhere from 8 to 20 percent, depending on the brand of clay used. If the culet is not seated properly, the clay will shrink unevenly around the stone and may result in its dislocation. Make room for the culet by creating a hole in the clay with a small tube or straw. Test the size of the tube needed by placing it over the culet. A tight fit around the very end of the culet’s tip is the right size.
Cabochon cuts are shaped and polished and feature a curved convex top with a flat back. A cabochon may be any shape, but ovals and circles are the most common.
- Use a tube with the same outside circumference as the stone to cut a hole in wet metal clay.
- Place the stone flat side down in the hole. The clay setting must be deep enough to hold the angled sides of the stone.
Metal Clay Settings
Several kinds of settings have been developed around the kind of cut, the kind of clay, or the point during construction that the setting is created.
- Stand-alone The setting is built and the stone is set in it separately from building the rest of the piece of jewelry. It is later added to wet or dry clay with paste, leaving a raised decorative setting. This method works well for faceted and cabochon cuts.
- Syringe A culet hole is made in wet clay as the jewelry piece is formed and the piece is dried. Syringe clay is used to create a setting for a faceted stone resulting in a lower profile than a stand-alone but still raised setting.
- Flush facet A culet hole is made in wet clay as the piece is formed. A stone setting bur, of the same diameter as the stone, is used to drill into the clay and the stone is set flush with the surface of the clay. This results in a low profile setting.
- Flush cabochon This technique needs to be limited to cabochons 8mm and smaller. A hole sized to accommodate the back of the stone is made in wet clay. The stone is placed in wet clay to the level where the dome’s curve begins. This offers a low profile setting where the top of the cabochon’s dome is slightly above the clay surface.
- Embeddable These settings are premade to accommodate faceted or cabochon stones. For a faceted stone, the embeddable will have a bottom layer that is placed into wet clay leaving a top “basket” above the clay to hold the stone. For cabochon stones the embeddable may be one piece of which the bottom half is pressed into wet clay. In either case, the stone is set after firing, thus providing a larger selection of potential stones.
Arlene Mornick is a Master Instructor for Art Clay World and teaches in the San Francisco Bay area. Her work can be viewed at www.lemordesigns.com.
“16 Important Facts About Setting Stones in Metal Clay” by Arlene Mornick originally appeared in the January/February 2016 issue of Lapidary Journal Jewelry Artist.
Make the Bracelet
Find complete instructions for making Arlene’s stone-setting sampler project, Linked Metal Clay Bracelet with Stones, in the Interweave store.
Learn More About Setting Stones in Metal Clay
Watch and learn, too! Now you can find multimedia instruction in how to set faceted stones in metal clay as you make a pair of faceted stone earrings in Darlene Armstrong’s online workshop, Getting Started Precious Metal Clay Series: Torch Firing Projects: Faceted Stone Earrings.
For additional information on Darlene and her other metal clay courses, check out these other posts:
Top 5 Metal Clay Tips from Darlene Armstrong
Torch Fired Metal Clay with Metalsmith and Jewelry Designer Darlene Armstrong
Torch Firing Metal Clay: Overcome the Fear of the Flame with Darlene Armstrong