4" Polished Agate Nodule with Wegeler Effect - Agouim, Morocco

The Wegeler effect, also known as the shadow effect or parallax effect, is a three-dimensional oddity in which rotating a banded agate creates the illusion that those banding lines move. One line will move with the source of light while the other moves with your point of view. This occurs in agate that has tightly packed, alternating bright opaque bands and transparent bands.

This site in Agouim, Morocco produces a wide variety of agate and jasper formations. Varieties such as jasp-agates and banded floater agates--a highly sought-after kind of agate with delicate bands appear between layers of formed crystals--can be found here. The site produces a diverse selection of other agates that are often confused with those from other sites like Aouli and Kerrouchen.