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Sterling Silver Clay Products

These clays offer the strongest final product, and becomes Sterling Silver when fired.

Basic Form: Lump
Sterling Silver - Lump Form

The basic clay material is called "lump form". It comes in a sealed foil packet and is ready to use. Lump form is used to roll slabs, snakes and to mold or sculpt objects. It can be thinned with water and used as a paste.

Sterling Silver Product Line


EZ960Sterling

This clay is an alloy consisting of 96% silver and 4% copper, and is the only sterling alloy on the market that is kiln fired on an open shelf, with no carbon required. EZ960 is a great, all purpose metal clay with excellent working properties. Because the clay is a sterling silver alloy, one of its best attributes is its post firing strength, in comparison to fine silver. This clay has a relatively low shrinkage rate at 10 - 11%.

Uses The inherent strength of EZ960 makes it the perfect choice for jewelry that takes lots of abuse, such as rings and bracelets. It is also great for jewelry with findings and components such as bails, hinges and clasps, as well as delicate pieces that would benefit from the strength of sterling silver.
Workability Ready to use directly from the package, the first thing you will notice is its smooth, creamy consistency. The clay takes texture with excellent clarity. It does not distort or stretch when removed from a mold, nor is it prone to tearing. It is easy to roll and form, and is surprisingly non-sticky. It also has a high moisture content, making it easy to work with in its wet form, as it stays workable and pliable without drying and cracking when forming, texturizing or molding. For best long term storage and to maintain hydration and workability, store unused EZ960 in a metal clay hydrator charged with distilled water.
Embedded
Objects
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 CZs and lab created gemstones can be fired at 1675F / 913C for 2 hours on an open kiln shelf (see Firing Schedule below) without failure or color change.
Firing
Options
After ensuring the clay is bone-dry, kiln fire on an open shelf at full ramp speed at any of the times and temperatures below:
Kiln Temperature & Hold Time:
1675F / 913C - 2 hours
1700F / 927C - 1 hour
1725F / 941C - 15 minutes
For low temperature kilns:
1650F /899C - 4 hours
1625F / 885C - 4hours
1600F / 871C - 8 hours
Torch: Not recommended

To prevent "sticking" on the kiln shelf, line the shelf with ceramic fiber paper (kiln paper) or, create a thin coating of crushed vermiculite on your kiln shelf. For objects that require special support: Vermiculite, pumice or alumina hydrate in a kiln safe container works well. We do not recommend fiber blanket, as it may stick to EZ960 during firing.

Items directly from the kiln will be slightly grayish in appearance, and is normal for an alloy of this type.

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.


Lump Form - PMC Sterling
PMC Sterling

This Precious Metal Clay comes out of the kiln as solid sterling silver. It is ideal for thinner, more delicate designs such as rings, findings and components which need the added strength of a silver alloy such as PMC Sterling. This alloy product is 92.5% fine silver and 7.25 copper. This clay has a shrinkage rate of 15 - 20%.

Uses Create stronger jewelry, findings and components with this clay. Perfect for rings. Due to its alloy strength, use less clay and make components thinner and stronger. Quality mark with .925 hallmarking.
Workability Workability is excellent with a smooth feel to the clay. If texturing the clay with a rubber texture, we recommend conditioning the clay with Slik, which will allow for a clean release of a texture. It is noticeably stronger even in the wet stage allowing it to be shaped and molded into smaller and more intricate lightweight pieces, ultimately using less clay. After tumbling for work hardening, the polish is beautiful and the final product is .925 sterling.
Embedded
Objects
Please review our Gemstone Firing Guide for information on which gemstones can tolerate a co-firing with PMC Sterling. Generally, any gemstone that can withstand kiln temperatures of 1500F/816C for 30 minutes can be embedded successfully with this clay.
Firing
Options
PMC Sterling is fired in a two stage process.
1. Fire for 30 minutes at 1000F/538C in open air on a kiln shelf to burn away the organic binders. Let cool.
2. Place in carbon in a stainless steel firing container. For best results, ensure 1/2" of carbon surrounds your article on all sides. Several pieces can be stacked, and fired together, if you maintain the 1/2" carbon between and around your pieces. Fire, at full ramp speed, at 1500F/816C for 30 minutes. For thicker, larger pieces, fire for one hour to ensure complete sintering, strength and durability.

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.


Metal Magic Sterling

This product has a shrinkage rate of approximately 25%, which allows for more detail in the final piece.

Uses This clay is excellent for highlighting details and texture. The shrink factor can be used as a design device to scale down larger forms or enhance details.
Workability Workability is excellent with a smooth feel to the clay. If texturing the clay with a rubber texture, we recommend conditioning the clay with Slik, which will allow for a clean release of a texture. It is noticeably stronger even in the wet stage allowing it to be shaped and molded into smaller and more intricate lightweight pieces, ultimately using less clay. After tumbling for work hardening, the polish is beautiful and the final product is .925 sterling.
Embedded
Objects
Cubic zirconia, lab created gemstones, bezel cups and other findings or embeddables can be co-fired with Metal Magic Sterling. Please refer to our Gemstone Firing Guide for a comprehensive list of gemstones that are compatible with the firing times and temperatures of Metal Magic Sterling.
Firing
Options
Kiln Fire - 2 Stage:
  • 1000F / 538C - 30 minutes (open shelf)
  • 1550F / 843C - 1-2 hours (activated carbon)

  • Cool in firing container, Do not crash cool.