The history of the zinc industry in Liège

Wallonia has subsoil that is rich in zinc in mineral form. The deposits of La Calamine (Moresnet) were considered during the 19th century, to be the most productive mine in Europe. The resources available on the left bank of the Meuse were just as remarkable.

In Europe, up to the beginning of the 19^th century, there was an important obstacle that prevented the transformation of such minerals into metals: the small difference between the melting point and the temperature at which zinc turns into a gas and evaporates on contact with the air.
 
In 1805, a major innovation was announced. A chemist from Liège by the name of Jean-Jacques Dony had discovered a solution to the problem of smelting zinc. His suggestion was to melt the zinc into long narrow moulds made of clay from the region of Andenne. These moulds would be extended by condensers. The smelting of the zinc would not take place in the open air, but in these cylinders filled with raw zinc in mineral form and with coal. Since air could not enter the cylinder, the melting of the zinc would take place perfectly.

This technique was invented during the Industrial Revolution, and it marked an important turning point for Belgian industry, especially for the industry in the Liège region, which was dependent on natural resources that were plentiful in Belgium. The new technique for smelting zinc allowed the metal that was produced to be commercialized for the European market. Beginning in 1809, Dony build his own factory in the Saint-Léonard neighbourhood, after obtaining the concession for the mine at Moresnet, that is, La Calamine. The name of the new mine was “Altenberg”, or in French, Vieille-Montagne. This was also the name of the company to which Dony surrendered his factory when his company went bankrupt. In 1837, the company of Vielle-Montagne, including mines and zinc smelting operations, was founded. It was the first multinational corporation in Europe, and it had two headquarters, one in Liège and one in Paris. Since 1989, following the gradual integration of the non-ferrous sector in Belgium, the company became part of the l'Union minière, and later part of Umicore.

The foundry at Saint-Léonard

Since Dony was from Liège, it was natural for him in 1809 to build his smelter in his home town. At that time, the location in the middle of the suburbs, Saint-Léonard and Vivegnis, was considered strategic. It was close to the coal it needed, and could draw on the technological and scientific expertise available in the city. But even with all that, the factory was a problem from the outset.

At the centre of a double movement of urbanization and industrialization, Saint-Léonard was a symbolic area. In the 19^th century its rapid industrialization led to a sharp rise in population, with an accompanying rise in social pressure. The plant was responsible for a number of major industrial nuisances, and many were critical for its operation. In the middle of the 19th century a conflict arose, which was referred to in the press as the “Saint-Léonard Affair”. There were many industries in the area, but only Vieille-Montagne generated clouds of smoke. Dony’s innovative procedure indeed allowed thick white smoke that contained a large amount of metal to escape into the atmosphere. Zinc oxide itself was not harmful to human beings, but the mineral that was smelted contained lead and cadmium, among other things.   When the metal in particulate form fell to earth, it killed plants (particularly in nearby vineyards) and caused other environmental damage. Animals were also at risk. No one could keep a dog near the plant; the smoke that lingered in the area killed them as well.