Gold Bulletin

, Volume 10, Issue 1, pp 10-14

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

The colour of gold and its alloys

The mechanism of variation in optical properties
  • K. E. SaegerAffiliated withDODUCO K.G.
  • , J. RodiesAffiliated withFriedrich Uhde GmbH


The optical properties of metals, and particularly their high reflectivity, are related to the effect on their free electrons of the energy of the incident light, but a satisfactory explanation of the characteristic colours of gold and its alloys and intermetallic phases has become possible only since calculations could be made of energy band structures.