Emphasizing its two trademark components this enameled shingle was described in the 1929 Sweet's Architectural Catalogue: "The base Armco ingot iron and the two coats of Pemco glass fused together at 1600 degrees F., produce a roofing tile extremely durable and of permanent beauty." (Sweet's Architectural Catalogue, 1929. Courtesy of The Sweet's Group, The McGraw-Hill Companies, Inc.)