Question

explain the use of copper in Gold jewellery​

Answer 1

Copper can be added to increase malleability. The strength of gold–nickel–copper alloys is caused by formation of two phases, a gold-rich Au–Cu, and a nickel-rich Ni–Cu, and the resulting hardening of the material. The alloys used in jewelry industry are gold–palladium–silver and gold–nickel–copper–zinc.

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