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Gold Bulletin

, Volume 43, Issue 1, pp 11–20 | Cite as

Metallurgy and processing of coloured gold intermetallics — Part II: Investment casting and related alloy design

  • Jörg Fischer-Bühner
  • Andrea Basso
  • Massimo Poliero
Open Access
Scientific Papers

Abstract

The attractive color of blue and especially purple gold alloys has always intrigued jewelry designers and producers. The reality of using these colors for jewelry has been very limited, however, mainly due to the inherent brittleness and poor corrosion resistance of this special class of gold alloys. The paper reports on some improvements in crack resistance that are obtained by particular additions to 14k blue- and 18k purple-gold colored alloys. Opportunities to incorporate such colors in jewelry design with these modified, colored-gold alloys using investment casting (as well as the still existing limitations) are discussed. Special attention is given to bi-metal casting technologies that can be used to manufacture multi-colored jewelry. A protective, transparent and wear-resistant coating finally needs to be applied to minimize corrosion and improve long-term stability of the colorful pieces.

Keywords

Fracture Resistance Gold Alloy Investment Casting Poor Corrosion Resistance White Gold 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© World Gold Council 2010

Authors and Affiliations

  • Jörg Fischer-Bühner
    • 1
  • Andrea Basso
    • 1
  • Massimo Poliero
    • 1
  1. 1.Legor Group SrlBressanvido (VI)Italy

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