Researchers from Spain have discovered what makes lustre (a metal/glass mixture produced in medieval times) shine. Researchers have found that lustre is made up of a thin layer of densely packed copper and silver nanoparticles in a glassy matrix. In medieval times, lustres were made in a wide variety of colors, such as red, brown, green, and yellow.

Trinitat Pradell and her colleagues used Rutherford backscattering spectroscopy and other techniques to show that the metallic shine of lustre comes from these nanoparticles. To understand the physical and chemical process involved in making lustre, Pradell’s group have reproduced lustre layers following the procedures listed in historical records. These metal/nanoparticle/glass layers will also be useful to today’s material scientists because they have many interesting non-linear properties.

Source:Metal nanoparticles lend glimmer to medieval artefacts | Nature