Cloudy BlackCloudy Black is an excellent natural stone material to use as pier caps in your outdoor areas. Pier cap is a decorative as well as utility element in outdoor construction and landscape designing. It must match with wall caps in the design. It means you have to install the same stone type as wall caps that you use for the pier caps. Piers columns are usually existing at the end or crossing points of retaining walls, seat walls, boundary walls, and