Split-faced concrete unit masonry is an architectural concrete masonry unit that costs a bit more than a standard CMU. It is made from a mixture of Portland cement, water, aggregates, and admixtures such as coloring agents, air-entraining materials, accelerators, retarders, or water repellents. Once shaped, compacted, and cured, the solid or hollow concrete units are then split crosswise or lengthwise. This random splitting allows some of the aggregate to break through in various planes, providing a look similar to natural stone.