From the latter half of the nineteenth century, Idar-Oberstein developed into an important centre of costume jewellery production. Numerous factories, large and small, produced costume jewellery for the world into the 1980s although today this trade has virtually lost its former significance. During that long time span, Idar-Oberstein was one of the four major German jewellery centres along with Pforzheim, Schwabisch Gmund and Hanau. Idar-Oberstein costume jewellery reflects each of the prevailing fashions in turn: Historicism, Jugendstil/Art Nouveau, Art Deco — to 1960s and 1970s Informel and Zero. Innovative handling of simple (inexpensive) materials soon led to an aesthetic that stood on its own merits, independently of 'real' jewellery. Here the Bengel company — with its sophisticated Art Deco jewellery — exemplifies innovative models and business policy. The author was able to study many early documents and photographs in Idar-Oberstein archives as well as pieces of jewellery that, taken together, are highly instructive on the history of costume jewellery. A vivid image of twelve jewellery manufacturers is evoked; proprietors and employees, production conditions, models policy, pieces of jewellery in each period style and worldwide marketing and distribution. Costume jewellery from Idar-Oberstein was not usually marked (stamped) because it was sold through wholesalers; this is what makes attribution to specific makers quite difficult today.