3" Coyamito Agate Geode Half - Chihuahua Mexico

Coyamito agate is among the most beautiful and rare of the Northern Mexican agates. Featuring blues, purples, browns, reds, and even sometimes pinks, Coyamito agate is most often found as small geodes.

Agate is a variety of microcrystalline quartz that displays translucence and in some cases banding. Agate primarily forms when silica-rich fluids fill pockets within rock and/or fossils, depositing the silica along the walls of the rock. This process can result in banding patterns as the composition and impurities of the fluids change over time. These banding patterns can either form as flat layers, creating formations known as waterline agates, or as more common rounded layers, depending on the surfaces available for deposition.