Johann C. Geiss (1771-1846) was born in 1771 and from around 1800 to 1846. During this time cast-iron jewelry was an inexpensive fashionable novelty for consumers in Europe and America. Cast iron jewelry peaked in popularity during Geiss's time from around 1800 to 1860. During the time it became the symbol of Prussian patriotism and resistance to Napoleon I in the Prussian War. Women even donated their gold jewelry to their country in exchange for iron. Often times the iron jewelry was inscribed ‘I gave gold for iron’. Transforming cast iron into a fashionable product was an important Prussian manufacturing success. Demand peaked in the 1830s for iron made jewelry when Berlin alone had 27 foundries. At the same time manufacturing spread to France and Austria. Geiss is a notable designer as he designed jewelry elements that could be individually cast then assembled at his workshop. Eventually, as his business progressed he opened his own foundry in Berlin.