Keokuk Limestone

Keokuk Limestone is a well-known, durable type of rock formed about 340 million years ago during the Mississippian period. It primarily consists of calcite, a mineral found in limestone, and was created from ancient marine organisms' skeletons and shells settling on the sea floor. This limestone is notable for its light gray color, smooth texture, and excellent ability to resist weathering, making it popular for building and construction, especially in bridges, monuments, and facades. It also played a significant role in regional industry and geology, serving as an important resource and offering insight into ancient marine environments.