The color characteristics of different copper alloys of particular interest in archaeometry (Cu-As, Cu-Sn, Cu-Sb, Cu-Ni) are investigated quantitatively and systematically. By using the CIELAB color system, different color parameters such as a*, b*, and L* were measured by a spectrophotometer in order to describe the surface color. This permits the establishment of a set of color-composition diagrams, demonstrating clearly the connection between chromaticity parameters and alloy composition.
With the evaluated data it is possible to start thinking about the role of color in technological choice, because it allows us to estimate the color of prehistoric metal artefacts with comparable compositions. A better understanding of the association between metallurgical alloy and color will aid the research of prehistoric metalwork because choices in production and use of metal were likely influenced by the particular qualities the material had to offer, of which color is an important one.