Trenwyth Franklin Stone™ by Echelon is a cast stone masonry product, which is used as an exterior veneer as a substitute for limestone and other natural stone products. Franklin Stone™ is made from a mixture of white portland cement, combined with fine aggregates, resulting in a highly dense product with a texture similar to that of natural limestone. Whether you prefer clean lines, or a bold chiseled finish, Franklin Stone™ CMUs can give you both. Unlike other masonry units, the aggregates do not show, giving Franklin Stone™ its consistent smooth natural stone finish.