Honeycomb weathering in sandstone
This type of weathering produces pits of varying size on a rock surface. The pits in the picture above are small approximately less than 1 inch up to 2 inches in diameter. This type of weathering is also known as tafoni, a Sicilian word for window. The dominant process that forms these features is probably chemical weathering. Sandstones are made up of sand size grains of quartz and other minerals. The grains are held together with a cement or glue such as quartz, calcite, or iron. In most instances, there are patches where the cement is no longer present allowing the grains to fall apart. Honeycomb weathering is abundant in the sandstones in the northern part of the state. This picture was taken of the Wedington Sandstone Member of the Fayetteville Shale in northwestern Arkansas.