Ruggles Mine
Ruggles Mine Road
Grafton, NH
A cathedral-like open pit near the top of Isinglass Mountain, where two centuries of mica and feldspar mining left a maze of tunnels, arches, and gemmy rock.
Near the top of Isinglass Mountain in Grafton, a mountainside opens into a huge man-made canyon of pale rock, its walls pierced by tunnels and spanned by natural-looking arches left behind by generations of miners. Ruggles Mine is one of the oldest mines of its kind in the United States, worked on and off since the early 1800s for the mica, feldspar, and other minerals locked in its coarse granite.
For much of the twentieth century it was a beloved rock-hounding attraction, where families climbed the mountain to explore the pit and carry home glittering sheets of mica and chunks of rose-tinted feldspar. Its hours have grown uncertain in recent years, so it is wise to check ahead, but the place itself, a bright open cathedral of stone high on the mountain, is like nothing else in New Hampshire.
What Guests Love
- Walking into a vast open pit ringed with tunnels and stone arches
- Hunting for mica, feldspar, and other minerals in the rock
- The dramatic, almost otherworldly setting at the top of the mountain
- The sense of stepping into one of the oldest mines in the country
Worth Knowing
- The mine has kept irregular hours in recent years, so confirm it is open before making the trip
- The access road up the mountain is steep and rough, so drive it slowly
- Footing on the mine floor is uneven rock, so wear sturdy shoes
- Weather on the exposed summit can change fast, and the tunnels stay cool and damp
Details
Grafton, NH
Learn about Ruggles Mine
Two centuries of mining
The story goes that Sam Ruggles began quietly mining mica here around 1803, reportedly shipping it to England and guarding the source so closely that he hid where his valuable mineral came from. Mica, sometimes called isinglass, was prized because it splits into thin, clear, heat-resistant sheets, useful for lantern and stove windows long before modern glass and later for electrical insulation.
Over the following century and more, the mine was worked for mica, and also for feldspar, used in ceramics and glass, and beryl and other minerals. Crews cut deep into the pegmatite, the coarse-grained granite that fills the mountain, leaving the tunnels, benches, and arches visitors wander through today. The mountain's name, Isinglass Mountain, comes straight from the mica that made it famous.
What the rock holds
The mine sits in a pegmatite, a kind of granite that cools slowly and grows unusually large crystals, which is exactly why it was worth mining and why it is a rockhound's delight. The most obvious mineral is mica, which peels off in flexible, shiny sheets, but the pit also yields blocky feldspar, smoky and clear quartz, and, for sharp-eyed collectors, rarer minerals.
For generations, part of the fun of a visit was the chance to pick through the rock and take a few finds home. Anyone poking at the walls should do so carefully and respect whatever collecting rules are posted, but the thrill of prying loose a bright plate of mica is the reason so many people remember Ruggles from childhood.
A cathedral of stone
What sets Ruggles apart from an ordinary quarry is its shape. Decades of digging opened a broad central pit with high walls, and the miners left pillars and spans of rock that read almost like the arches and columns of a ruined cathedral. Sunlight pours into the open floor while the side tunnels stay dim and cool, and the contrast gives the place its strange grandeur.
The setting adds to the effect. The mine sits high on the mountain, so the approach climbs steeply and the views open up as you near the top. Standing in the bright pit, surrounded by pale stone and dark tunnel mouths, it is easy to feel very far from the ordinary world below.
Closest Boutels
The closest Boutel™ stays, so you can turn this stop into an overnight. Each is an independently owned, editorially selected place to stay.
Things to Do Near Grafton
Canaan
About 8 miles, a 15 minute drive
A small western New Hampshire town with a historic street of white clapboard buildings on Canaan Street Lake.
Mascoma Lake and the Dartmouth region
About 15 miles, a 25 minute drive
Quiet lakes and the college town of Hanover, home to Dartmouth College and its museums, lie to the west.
Cardigan Mountain
About 12 miles, a 25 minute drive
A popular bare-summit hike with wide views over the western hills, reached from the Grafton area.