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PMC Silver Clay Products

Silver Alloy Clay Products

PMC PRO and PMC Sterling are silver alloy clays, and are the latest innovation in metal clay formulas. These clays offer the user the strongest final product, comparable to sterling silver. When fired, they are nearly indistinguishable from a cast object. The silver content of PMC PRO silver alloy clay is 90%, and the silver content of PMC Sterling silver alloy clay is 92.5%. Because these two products are alloys, and have up to 10% copper content, they must be fired with carbon, and must be fired in a kiln.

The Basic Form: Lump
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. Lump form can be thinned with water and used as a paste. PMC PRO and PMC Sterling come in lump form only.

PMC Silver Alloy Product Line
PMC PRO Silver Alloy Clay

This product is 90% fine silver and 10% binder by weight. PMC PRO shrinks about 15% to 20% of its original size during sintering. Objects made from this version are very strong. PMC PRO can withstand dapping, bending, forming and soldering. Kiln fire only in carbon for a minimum of 1 hour, or for the strongest, most durable product, fire for a full 2 hours @ 1425F.

Uses PMC PRO offers the most versatility of any other silver clay type. The strongest of all metal clays, PMC PRO can be rolled very thin for delicate ring shanks, findings and settings.
Workability PMC PRO has very good working properties and does not dry out as quickly as some other clays. Water can be added to extend the working time when the clay begins to stiffen.
Any object that can withstand the firing temperatures and times of PMC PRO can be embedded and fired in place. Some, but not all natural gemstones, lab gems, cubic Zirconia and porcelain can be used.
Kiln Temperature/Hold Time:
Option 1: 1425F/1 hour (small pieces); 1400F/1 hour
Option 2:
Step 1 - Burn out - 1400F on open kiln shelf/30 minutes
Step 2 - Bury in carbon and fire at 1400F or 1425F/1 hour
Torch: Not recommended
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.

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.
Please review our Gemstones Firing Chart for information on which gemstones can tolerate a co-firing with PMC Sterling. Generally, any gemstone that can withstand kiln temperatures of 1500F for 30 minutes can be embedded successfully with this clay.
PMC Sterling is fired in a two stage process.
1. Fire for 30 minutes at 1000F 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 for 30 minutes. For thicker, larger pieces, fire for one hour to ensure complete sintering, strength and durabilty.