Description | The Redwall Limestone is one of the most distinctive formations in the Grand Canyon, responsible for many of the alcoves, buttes, and mesas seen. It has a medium gray color on a freshly exposed surface, but is often stained red due to overlying formations. It is a pure calcium carbonitic rock, containing little sand and shale particles. Some red jasper are also found near the bottom of the formation. The purity of the limestone indicates that this formation was deposited in a shallow, quiet sea. |