rbrunell:
There are guidebooks for this sort of thing. I don’t know of
anything current and the more up to date the better, as
collecting and mining areas close and change over the years. I
would check the library, the GIA bookstore (they have a toll free
number in Carlsbad, California, and Books in Print. I do know
there are one or two books by June Culp Zeitner about northeast
collecting sites. Can’t remember the states covered and the
books are old, but probably quite accurate as she has a good
reputation.
If I were you, I would also check with my local Gem and Mineral
Society as those are the local people who really know about
collecting sites.
There is definitely famous tourmaline at Newry, Maine, but I
believe the mine is privately owned. There is also garnet at
Gore Mountain in the Adirondacks and i believe there are some
collecting sites, but, living in the South myself i don’t know
exactly where. Again, the local Society or a local rock shop
could probably tell you where. Another resource would be the
Lapidary Journal Index. This magazine has carried reports of
collecting sites and field trips for years. Hope this helps.