Synthetic colorant, c 1900.

GERMANY - JULY 28: A jar of Homophosphine G synthetic dye manufactured by Farbwerk Mülheim A. Leonhardt & Co, Mülheim-am-Main, Germany. August Leonhardt and Leo Gans set up a dye factory at Fechenheim (near Offenbach) in 1870. After the partnership broke up, Leonhardt established another dye factory in the neighbouring town of Mülheim-am-Main in 1879. It became a limited company as Aktien-Gesellschaft Farbwerk Mühlheim vorm. A. Leonhardt & Cie. in 1895. Part of a collection of late nineteenth and early twentieth century colorants transferred from the Colour Museum, Bradford, in 1985. (Photo by SSPL/Getty Images)