For 100 years, iron oxide pigments from Krefeld-Uerdingen, Germany, have added colorful accents to concrete – from traffic areas and façades to urban open spaces. The foundation was laid in 1926 by the chemist Julius Laux. He was searching for a way to make use of iron oxide, that was a byproduct of the target aniline production. The Laux process, named after him, produces not only aniline but also iron oxide pigments with consistent color intensity, high quality, and reproducibility – with virtually no waste. This early form of the circular economy was the starting point for the success of Bayferrox iron oxide pigments in the construction industry.