Want more on FS999 and its firing properties including firing with gemstones?
Click hereFire open shelf on a raised ceramic kiln shelf at 1650°F / 900°C - 2 hours, full ramp. No carbon required. Shrinkage: 13%
Cubic zirconia, lab created gemstones, bezel cups and other findings or embeddables can be co-fired with FS999. Please refer to our
Gemstone Firing Guide for a comprehensive list of gemstones that are compatible with the firing times and temperatures of FS999. Most, but not all, cz’s and lab created gemstones can be fired at 1650°F / 900°C for 2 hours on an open kiln shelf (see Firing Schedule below) without failure or color change.
After ensuring the clay is bone-dry, kiln fire on a hard kiln shelf raised up from the kiln floor. Fire at full ramp speed at any of the times and temperatures below:
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.
After ensuring the clay is bone-dry, kiln fire using a firing vessel filled with coconut, coal or magic carbon. Place container on a raised kiln shelf. Use the two stage firing method below:
Full ramp to 1000°F / 537°C – hold for 30 minutes, then full ramp to 1650°F / 900°C – hold for 3 hours.
We recommend kiln firing.
During firing, FS999 will shrink 13% as a result of the sintering process, as the organic clay binders burn off in the kiln.
When finishing, FS999 provides either an easy satin finish, or if you like, a beautiful mirror finish.
For a satin finish, brass 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.
FS999 is an excellent choice for enameling. Like all fine silver, FS999 accepts both transparent and opaque enamels beautifully.
To achieve a good, dark result from Liver of Sulfur (LOS) or Patina Gel, ensure your piece is absolutely 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, FS999 is metallurgically just like other fine silver metals, but like other fired metal clays, it is more porous than sheet stock or cast items. Due to this porosity, FS999 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 FS999 by using the same flux, solder and torch(es) as you would to solder other silver products or gold.
Hallmark as .999 FS or Fine Silver