Polished gold

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Polished gold decoration on porcelain. The details of the bird were only carved out by polishing with the agate pencil.

Polishing gold is a type of precious metal decoration for porcelain, which has to be polished after the decor firing if it is to shine. That is why it is also called unpolished gold. Polished gold is an on-glaze decoration.

Polished gold

Polished gold is made as a suspension of turpentine oil , precious metal powder and compounds of lead and bismuth. The gold content is between 11% and 30%. The color of the polished gold is determined by adding silver. It is black and runny during processing. Polishing gold forms a layer about three to six µm thick on the body. This makes it more durable than bright gold . It is fired at a firing temperature of approx. 800 ° C and comes out of the muffle furnace with a dull, gold-colored surface . Polishing with a fiberglass brush or sand gives the polished gold a matt sheen. A strong shine is achieved by polishing with an agate pencil or blood stone . Polishing also increases the strength and resistance of the gold layer.

Polished silver

Polishing silver contains between 20% and 70%, usually 55% silver. It is fired at 820 ° C to 850 ° C. The production and processing is otherwise analogous to that of polished gold. Since the polishing silver because of its tendency to form silver sulfide starts , there are also polishing silver with gold and platinum shares.

Polished platinum

Polishing platinum is available in different compositions. It either only contains platinum or gold is mixed in with it. It has a white gold color and is manufactured and processed in the same way as polished gold.

One of the most common uses for burnish silver and burnish platinum today is in electronic circuit printing .

literature

  • Wolf E. Matthes: Ceramic glazes: basics, properties, recipes, applications ; 2. through Edition; Augustus Verlag, Augsburg; 1990
  • Ekkehardt Kraemer (ed.): Saxon-Thuringian manufactory porcelain. Glass ceramic. Publicly owned foreign trade company of the German Democratic Republic, Berlin 1985
  • Hermann Heuschkel, Gisela Heuschkel, Klaus Muche: ABC ceramics ; 2. heavily revised. Ed .; German Primary industry publisher; Leipzig; 1990