In 1894, the silica and kaolin mine was first opened. In 1911, a plant was also built on the site. Discovered accidentally when a well was being dug on a farm owned by Philibert Tassé, the operation was dry-mined and produced a fine dust extremely dangerous to breathe. Quite a few people developed the lung disease silicosis, which results in death. As a result, the plant’s activities eventually ceased in the 1940s. As you drive along, you may notice a white dust on the ground along the Chemin de Rockway Valley: this is kaolin.