Here is a rare mineral from a modern world class location - Mont St. Hilaire in Quebec. The quarry is known to have more than 370 minerals and is type locality for at least 50 minerals. The quarry has been worked since the 1950's and in later years has been in and out of operation. Currently the mineral and gem club of Montreal hosts 2 or 3 field trips a year to the quarry. The quarry is not being actively mined and it is difficult to find anything of quality. An active quarry is a field collectors best friend.
Our goal for the past 10 years has been to visit at least one classic mineral locale per year. I was unable to attend the Mont St. Hilaire trip but John did trek up there and came back with some massive serandite and a few other minerals.
Field trip information: Excursions
Additional information about Mont St Hilaire
Mont Saint-Hilaire | Gault Nature Reserve - McGill University
ALKALI-NUTS, Mont Saint-Hilaire site, entry page