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Of gold and silver thread

in diamond die

The special status of the Souveraineté de Dombes, of which Trévoux was the capital, enabled the establishment of an advantageous tax system, making the town the Monaco of the Lyon region in the 17th and 18th centuries. These favorable conditions attracted gold and silver miners and silversmiths from Lyon. Later, in the 19th century, metal drawing was refocused, no longer on wire manufacture, but on the tool used to stretch it: the diamond die.

Gold and silver printing

Located outside the Kingdom of France, the Princes Souverains de Dombes were careful to foster the development of the local economy through a number of advantages over neighboring territories. For example, the working of precious metals was much less taxed than in France, and it was possible to own a private arg. This machine was used to stretch gold and silver rods before turning them into thread for embroidery and trimmings. In France, there was a state monopoly on the argues royales, located only in Paris and Lyon, from which taxes had to be paid in order to stretch the precious metal. Gold and silver drawers therefore established themselves and prospered in Trévoux until the 19th century. Indeed, even after the Dombes region became part of France in 1762, the industry continued to thrive, as the king established a royal argue in Trévoux to preserve this activity.

The diamond die

During the 19th century, the metal-drawing industry was reformed and, in Trévoux, the manufacture of dies was developed. This is a drilled tool through which metal is passed to stretch it. More precisely, a wire that is too large is passed through a hole that is too small, forcing it to reduce its diameter. Given the high level of friction, the die wears out and needs to be replaced regularly. This is why diamond dies were developed around 1850. A drilled diamond is set into the die, through which the wire passes. As diamond is very hard, it wears much more slowly and the die lasts longer. This productivity gain was particularly welcome in the context of the advent of electricity, which required the drawing of large quantities of tungsten and molybdenum for light bulb filaments, or copper to conduct the current.