 Steel was an even better structural material than wrought iron, and new steel making processes developed in the late 19th century greatly lowered the cost of production to far below the cost of wrought iron.The widespread use of cast-and-wrought iron frames in multi-level buildings was translated into steel-frame buildings, and was an essential step in the development of the modern skyscraper.In Europe, cast iron had been occasionally used with architectural embellishment in the middle ages, such as fire backs with cast figures and scenes.