Underground mining and pyrochlore ore processing at Niobec Mine, Quebec, Canada

The property of the Niobec mine is located i n the St-Honor@ carbonatite complex near Chicoutimi; located 525 km north of Montreal, Quebec. The original discovery of the carbonatite complex was made by the Société Quebeçoise d’ Exploration Miniére’ (SOQUEM) in 1967 as a result of an airborne radiometric survey in search of uranium deposit. With the exploration of the complex, a rare earth zone was first exposed followed by the discovery of two niobium zones. The ore concentration process was jointly developed by the Quebec Department of Natural Resources Laboratories and SOQUEM after an intensive bench and pilot plant testing. Even though the deposit contains several useful minerals, only two of them, pyrochlore Na Ca Nb2O6 F and columbite (Fe, Mn) (Nb, Ta)2O6, are recovered at the present time. The construction of the underground mine and mill complex with an initial milling capacity of 1,360 metric tons/day (1,500 tons/day) was completed in 1976. Since the construction, the original capacity was gradually increased to 1,590 metric tons/day (1,750 tons/day) and then in early 1981 after a major expansion to 2,086 metric tons/day (2,300 tons/day). (AU)