Metal clay

Metal clay is a crafting medium consisting of very small particles of metal such as silver, gold, bronze, or copper mixed with an organic binder and water for use in making jewelry, beads and small sculptures. Originating in Japan in 1990, metal clay can be shaped just like any soft clay, by hand or using molds. After drying, the clay can be fired in a variety of ways such as in a kiln, with a handheld gas torch, or on a gas stove, depending on the type of clay and the metal in it. The binder burns away, leaving the pure sintered metal. Shrinkage of between 8% and 30% occurs (depending on the product used). Alloys such as bronze, sterling silver, and steel also are available.

Metal clay first came out in Japan in 1990 to allow craft jewelry makers to make sophisticated looking jewelry without the years of study needed to make fine jewelry.

Fine silver metal clay results in objects containing 99.9% pure silver, which is suitable for enameling. Lump metal clay is sold in sealed packets to keep it moist and workable. The silver versions are also available as a softer paste in a pre-filled syringe which can be used to produce extruded forms, in small jars of slip and as paper-like sheets, from which most of the moisture has been removed. Common brands of silver metal clay include Precious Metal Clay (PMC) and Art Clay Silver (ACS).

Metal clay artists looking for more strength in their silver creations can also mix PMC fine silver clay with an equal part of PMC Sterling clay. The firing of this alloy is found to be up to 898 °C (1650 °F) for two hours.

Another available alloy, EZ960™ Sterling Silver Metal Clay was invented by Bill Struve from Metal Adventures, the inventor of BRONZclay™ and COPPRclay™. 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 is fired open shelf on a raised hard ceramic kiln shelf at 1675 °F / 913 °C – 2 hours, full ramp. No carbon required. Its shrinkage rate is smaller than other clays, at 10–11%.

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