Illusion is an innovative style in jewelry making, which enhances the appearance and especially the perceived size of jewelry diamonds. Specifically, jewelry in this technique uses a small diamond enclosed in a precious metal that is designed to mimic the faces of a diamond. The small diamond in the center provides shine and at the same time reflects the design of the metallic pattern.
As the name of this technique suggests, from a distance it creates the "illusion" that you are seeing a really much larger diamond. There is also another alternative way of placing stones that creates the illusion of a larger diamond, called cluster-illusion. This is a technique where many small diamonds are placed very close to each other to create the appearance of a single stone. If you look at such a ring from a distance, the effect created by the shine of small diamonds gives the impression of a large single stone.