Vieille Montagne is the name of a former zinc mine in Kelmis (La Calamine), a town in Belgium between Liège and Aachen. The mine's name is French for "the old mountain", and this is also reflected in its German name, Altenberg (earlier, Alten Galmei-Berg). The mine was once a bone of contention between Germany on the one side and the village that became the neutral territory of Moresnet.
The mine was first opened in 1805 and continued its operation until the end of the nineteenth century, when a workforce of 300 produced 8,500 t of crude zinc annually.
The company opened a second zinc mine in Zinkgruvan in Sweden, which is still in operation. It also ran a harbour in Åmmeberg to ship the zinc. The company also had mines in the UK in Nenthead, a village in Cumbria, which were worked from 1896 until 1949. In the department of Ariège in France the VM company took the lease on the zinc mines at Bentaillou in the Pyrenees, also after World War II.
The name became synonymous with zinc oxide and with rolled zinc, especially for building applications. The company was the world's oldest and also largest zinc producer, producing at its peak at least 149,000 tonnes per year. In 1989 Vieille Montagne was merged into the Union Minière group, based in Belgium, which became Umicore in 2003. The group continues its rolled zinc activity under the brand VMZinc which still refers back to the historical link with Vieille Montagne.