I've had the pleasure of exploring and collecting in some mines and I like seeing the old images. Thanks for posting those and SPQR for posting that great cover. I've a small collection of postcards showing mines. Here are a couple. My apologies for the low resolution scans.
Mt. Mica in Paris, Maine is a well known locality for beryl, tourmaline, and lithium minerals.

The old Rockport Granite Co. quarry in Rockport, Massachusetts closed in 1929 and the quarry was allowed to fill with water. It is immediately next to the ocean and is now part of the beautiful Halibut Point State Park.
