Synthetic colorants, c 1900.
© Science Museum / Science & Society Picture Library
Six jars containing synthetic colorants. Blue Lilac 20 manufactured by G. Siegle & Co. of Stuttgart; Guinea-Rot (red) SDG by Actien Gesellschaft fUr Anilin Fabrikation, Berlin, Germany (Agfa); Ultramarine 9 by Siegle; Guinea Echtgelb 3G by Agfa; Imitation Vermilion 3 by Siegle; Vermilion 00 by Siegle. The Guinea dyes were introduced by Agfa in the early 1880s. Ultramarine (blue) and Vermillion (red) are traditional pigments. Ultramarine is a natural blue mineral which is rare but ultramarine has been made synthetic since the early nineteenth century. Vermilion is a red form of mercury (II) sulfide (as in the ore cinnabar). The Aktien Gesellschaft fUr Anilin Fabrikation was founded in 1873 by Carl Martius and Paul Mendelssohn-Bartholdy (the nephew of the composer), became part of I.G. Farbenindustrie AG in 1925 and a subsidiary of Farbenfabriken Bayer AG in 1952. In 1873 the Stuttgart firm Heinrich Siegle was acquired by BASF. In 1889 Gustav Siegle (the son of Heinrich Siegle) bought