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DICHORIC GLASS: The brilliant dichroic optical properties of dichroic glass are the result of multiple micro-layers of metal oxides. These thin layers of oxides have a total thickness of three to five millionths of an inch.
NASA developed dichroic glass for use in satellite mirrors. Multiple ultra-thin layers of different metal oxides (gold, silver, titanium, chromium, aluminium, zirconium, magnesium, silicon) are evaporated on to the surface of the glass in a vacuum chamber.
The resulting plate of dichroic glass can then be fused with other glass in multiple firings. Certain wavelengths of light will either pass through or be reflected, causing an array of colour to be visible. Due to variations in the firing process, individual results can never be exactly reproduced; each piece of fused dichroic glass is unique. COE: This rate, which is commonly known as the Coefficient of Expansion (COE), is usually expressed as a whole number, rather than as a long decimal figure. Most Bullseye glass, for example, is said to have a Coefficient of Expansion of 90, and you will often hear glass artists refer to it as COE90 glass. Spectrum, another common glass, has a COE of around 96. All COE glass must be the same before fusing (Example 90 Bulleye Clear glass with 90 Dichroic glass). Two glasses with considerably different COEs are incompatible. They cannot be fused together and should be kept in separate areas of the glass studio to prevent their accidentally becoming intermingled. Enameling: Enameling is the art of applying a vitreous material (powdered glass) to an object, as decoration, to the surface of which it is made to adhere by heat. Metals are the usual foundations to which enamels are applied, but stone, earthenware, and glass may be enameled. When one speaks of an "enamel," we understand it to mean a metal that is ornamented by a vitreous decoration fused and fixed to the metal surface by heat. Silver Metal Clay (PMC or Art Clay). Metal clay is a clay-like medium used to make jewelry, beads and small sculpture. It consists of very small particles of precious metals (such as silver, gold or platinum) mixed with an organic binder and water. Metalclay can be shaped just like any soft clay, by hand or using moulds. After drying, it is fired in a kiln, with a handheld gas torch, or on a gas stove. The binder burns away, leaving the pure, sintered metal. Shrinkage of between 8% and 30% occurs (depending on the product used), but this is exploited by artisans to produce very fine detail.
Silver precious metal clay results in objects containing .999 pure silver which is ideal for enamelling. Silver Findings: The precious metal trade is been driven up by the govnernment metals people in the USA as they once did in the 80's. On the news we where told it was the Chinese that where buying up all the silver, but it is not true. Our country drove the price up. |
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