Firescale

Firescale

Firescale, also known as firestain, is a red or purple stain that appears on mixtures of silver and copper, such as sterling silver. At high temperatures, oxygen mixes with the copper to form cuprous oxide and then cupric oxide. Attempts to reduce this problem usually involve replacing oxygen with another gas such as hydrogen or ammonia.

With a very high copper content, this may appear on gold mixtures.

External links

*http://www.silversmithing.com/1fire.htm


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • Argentium sterling silver — is a modern sterling silver alloy which modifies the traditional sterling silver alloy (92.5% silver + 7.5% copper) by replacing some of the copper with the metalloid germanium.Argentium Silver is the result of research by Peter Johns at the… …   Wikipedia

  • Silver — This article is about the chemical element. For the color, see Silver (color). For other uses, see Silver (disambiguation). palladium ← silver → cadmium …   Wikipedia

  • Sterling silver — is an alloy of silver containing 92.5% pure silver and 7.5% other metals, usually copper. The sterling silver standard has a minimum millesimal fineness of 925. Fine silver (99.9% pure) is generally too soft for producing large functional… …   Wikipedia

  • Germanium — (pronEng|dʒɚˈmeɪniəm) is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, silver white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. Germanium has five naturally… …   Wikipedia

  • Boric acid — Boric acid …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”