Schiller which comes from the German word for 'twinkle' is an
optical phenomenon which is also known as
adularescence. It's only produced when light interacts with the internal microstructures of a
mineral and is not a property of the gemstone or mineral itself. When schiller is visible in
labradorite, the effect is sometimes referred to as labradorescence as this mineral is particularly well known for its
iridescent qualities.
