schiller
n. uncountable C2 Proficiency US //ˈʃɪɫɝ// UK //ʃˈɪlɐ// schiller
n. a shiny or sparkling look on the surface of some minerals. It happens when light reflects off tiny layers inside the stone.
n. an iridescent or metallic lustre caused by the reflection of light from minute inclusions or internal planes within a mineral. Often observed in minerals like labradorite or hypersthene.
The stone has a beautiful blue schiller when you turn it.
The geologist identified the specimen by the distinct golden schiller visible beneath its polished surface.
While the base colour of the mineral remains dark, the presence of schiller creates a play of light that shifts between copper and violet as the viewing angle changes.
Usage
Typically used in mineralogy to describe optical phenomena in crystals.