Cubic zirconia, lab created gemstones, bezel cups and other findings or embeddables can be co-fired with EZ960. Please refer to our
Gemstone Firing Guide for a comprehensive list of gemstones that are compatible with the firing times and temperatures of EZ960. Most, but not all, cz’s and lab created gemstones can be fired at 1675°F / 913C for 2 hours on an open kiln shelf (see Firing Schedule below) without failure or color change.Glass or dichroic gems are not compatible with the firing schedule of EZ960 and must be set after firing.
While torch firing is technically feasible, it is not recommended. After ensuring the clay is bone-dry, fire on a open shelf raised above the kiln floor at full ramp speed at any of the times and temperatures below:
For low temperature kilns:
Fire on a raised hard ceramic shelf. For objects that require special support, we recommend using vermiculite or pumice in a kiln safe container. We do not recommend fiber blanket, as it may stick to EZ960 during firing. The use of a hard ceramic kiln shelf is recommended and will prevent sticking. Items directly from the kiln will be slightly grayish in appearance, and is normal for an alloy of this type.Note: Older kilns with heating elements in the bottom of the kiln require a raised shelf to properly fire.
Note: Muffle kilns have heating elements on three sides (no heating element in the door), therefore any air leakage around the door can create cool spots near and around the door. For this reason, to ensure complete sintering, we recommend firing all metal clays in the rear center portion of the kiln.
During firing, EZ960 will shrink 10% to 11% as a result of the sintering process, as the organic clay binders burn off in the kiln. This relatively low shrink-rate, combined with the inherent strength of Sterling, makes EZ960 an excellent candidate for rings and bracelets, delicate items, or other jewelry that may be subject to heavy wear.
When finishing, EZ960 provides either an easy satin finish, or, if you like, a beautiful mirror finish.
For a satin finish, steel brush your piece directly out of the kiln, followed by 1 to 2 hours in a rotary tumbler. A magnetic tumbler will drastically reduce the time needed in a tumbler.
For a mirror finish, use the same process as above. Then, using a flex shaft or other rotary tool, polish with radial bristle discs and, lastly, silicone polishing wheels and points.
When enameling over silver, most enamelists choose fine silver as a base, as it does not require depletion guilding prior to firing enamels. Having said that, after firing, EZ960 can be enameled, however results are not identical to fine silver. Despite being a sterling alloy, it does not require depletion guilding prior to enameling when using opaque enamels, and will provide good results. Transparent enamels can also be used, however, some color distortion or cloudiness may occur due to copper oxides in the alloy. We recommend depletion guilding prior to using transparent enamels. For all enamels, the prep work, firing sequences and firing schedules are the same as with fine silver. Choose EZ960 for accent enameling or the use of opaque enamels on rings, bracelets, or wherever an alloy or additional strength is desired.
To achieve a good, dark result from Liver of Sulphur (LOS), Patina Gel or Black Max, ensure your piece is clean by soaking and then brushing with hot water, soap, and ammonia. Using a strong solution of LOS in very hot distilled water, dip or soak your piece in the solution until you get the darkness or result you desire. Adding a teaspoon of ammonia to your LOS bath can also help achieve a darker result or, possibly, a rainbow effect. A bath of baking soda and water will neutralize the LOS bath and halt the patination process. Then, either by hand or by machine, bring up the high points with a polishing cloth, Scotchbrite™ pad (satin finish), or polishing wheels (high shine or mirror finish).
Once fired, EZ960 is metallurgically just like other sterling silver metals, but, like other fired metal clays, it is more porous than sheet stock or cast items. Due to this porosity, EZ960 will “soak up” solder. When possible, prepare areas for solder by burnishing to close the open pores and reduce the tendency to absorb solder. Join other metals and findings to fired EZ960 by using the same flux, solder and torch(es) as you would to solder other silver products or gold.
Hallmark as Sterling.