metallic lustre
(US metallic luster)
noun
1The sheen characteristic of (especially polished) metals and certain opaque minerals.
2A similarly shiny or iridescent appearance in certain organisms, especially insects.
3 Ceramics a reflective or iridescent decorative finish produced by applying a thin film of metal to the surface of the glaze.
Origin
Late 18th century; earliest use found in Encyclopaedia Britannica.