Talc processing factory. Worker inspecting talc powder produced by crushing machinery at a talc processing factory. Talc (hydrated magnesium silicate) is a very soft mineral that is the main component of talcum powder. After being quarried, the rock is crushed into powder form and is also used in paper, plastics, cosmetics and paints. This factory is on the edge of the talc quarry in Luzenac, France, the largest talc quarry in the world. The quarry is at an altitude of 1800 metres altitude in the Ariege region of France. Founded in 1905, it produces 400,000 tonnes of talc in a year.