Nova Scotia had several historical tungsten mines. It is used as filaments in lightbulbs. It is the metal with the highest melting point (3,422 °C) so it is often mixed with other metals to make alloys that have high temperature tolerance, high corrosion resistance and excellent welding properties. These superalloys are used in the aerospace and automotive industries in things like airplane turbine blades and wear-resistant parts and coatings.
Here are the stories of some Nova Scotia tungsten mines:

Joe Cope and Goffs Tungsten * Indian Path * Moose River * Lower Sackville