4.4" Polished Banded Agate Nodule Section - Aouli, Morocco
This is an unusual, polished agate nodule section that was collected from Aouli, Morocco. It features pastel-white, opaque banding with small red fractures, as well as what appears to be pre-existing aragonite or rutile crystal formations along one edge. One side of this specimen has been cut flat and polished to a glossy finish, while the other side and outer edge have been left rough.
Agate is a variety of microcrystalline quartz (chalcedony) that displays translucence and in some cases banding. Agate primarily forms when silica-rich fluids fill pockets within rock and/or fossils, resulting in deposition of 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 or rounded layers, depending on the surfaces available for deposition.