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MINING FOR INDICOLITE TOURMALINE
Collecting at the Blue Pit on Plumbago Mountain in Newry, Maine

by Eric Greene

THE PLUMBAGO MOUNTAIN STORY
Newry Hill, a spur off Plumbago Mountain, is the most prolific tourmaline producer in Maine. Since its discovery in 1898, production from the mine has exceeded thousands of kilograms of high-quality tourmaline. Then, in August 1972, three amateur mineral collectors traveled to Newry, Maine for a weekend of digging to see if they could find any tourmaline. They hit a series of small pockets containing gem crystals that were so promising that they leased the property, and in October opened some major pockets. This was to become the largest discovery of gem tourmaline in the world, producing one metric ton of fine-quality tourmaline, consisting of many variations of colors never seen before. Overnight, the lives of the collectors who made this legendary find were changed forever.


Plumbago Mountain seen from the front seat of a 4x4 pickup

THE FIRST FIELD TRIP: AUGUST, 2011
It was a warm August morning when I joined my long-time collecting partner Dick Holmes for our first ever collecting trip to this historic mine. We were part of the 30-person strong expedition mounted by Woody Thompson of the Maine Geological Survey, with the 30 lucky collectors having been drawn by lottery. You can imagine our excitement as we made the four mile drive from the Plumbago Mountain Farm house at the bottom up a rugged four-wheel drive road to the top of Newry Hill. Though we knew if wouldn't really happen, we couldn't resist entertaining visions of a multi-million dollar tourmaline find through the entire drive up the mountain, our excitement mounting like little kids on Christmas Eve.


View south from Newry Hill overlooking the Blue Pit workings

At the end of the drive, we climbed the final steep, rocky stretch of road to the crest of Newry Hill. On the very top, we picked a convenient parking spot near the digging areas, and then rushed off to scout around. The weather was perfect - about 70º F, and not a cloud in the sky. I was bubbling over with excitement and wonder and anticipation at just being here at this famed locality that I had read about dozens of times, pouring over the words and drooling over pictures of crystals like the luscious watermelon tourmalines from the Dunton Quarry. I had to pinch myself - was this real?


Roped off workings at the Blue Pit

Dick and I worked in the sun as the temperature climbed into the 80s, scouting for boulders to crack open that showed signs of blue tourmaline. As you can see in the photos, the outer margins of the site were dotted with large chunks of rock which had been blasted free as the miners hunted the elusive gem pockets. The bulldozer and/or backhoe were used to move these large chunks, sometimes over six feet in length and width, away from the mining area and out of the way. Sometimes, along the edges of these rocks, areas rich in blue tourmaline were exposed and smaller, specimen-sized pieces could be extricated with some heavy hammering and chiseling. Smaller pieces, up to two to three feet across, were a little easier to break up in the hunt for blue crystals - especially when the matrix rock was cleavelandite, which splinters fairly readily when attacked with a 16-pound hammer.


Dick Holmes uses his one-pound trim hammer to takes out some indicolite tourmaline

We found tourmaline crystals in two different matrixes: In white to tan bladed cleavelandite, and in smoky quartz. Of these, the crystals in quartz were better formed, though neither was gemmy. Many of the largest crystals, up to 8" long and over an inch in diameter were "rotten", meaning that the tourmaline was very crumbly. This may be the result of exposure to corroding fluids after the crystals were formed.


Rockin' Robin (our tour guide) and friend supervise from the shade of an umbrella

During the course of the day we moved 360º around the outside of the Blue Pit, which was cordoned off as it had been declared out of bounds. This did not present much of a problem, as there were more tourmaline-laden boulders than we could have broken up in a week of hammering, not to mention that we had to keep in mind that the springs on the truck would be groaning if we amassed too heavy a load. By lunch time we had filled several five-gallon buckets with tightly trimmed specimens, wrapped in newspaper to prevent damage.


Another view of recent workings in the Blue Pit

After a short lunch break the afternoon flew by, as we moved from boulder to boulder, hammering and chiseling and splitting rock to remove the prized pieces displaying shiny, indigo blue tourmaline. On this trip, at Dick's suggestion, I used a one-pound geologist's hammer for final trimming (the kind with a square face for hammering at one end, and a sharp point at the other end). This meant there were fewer pieces smashed to smithereens, though we still lost a good number, as some destruction is inevitable when field trimming.


Diggers take a break to enjoy the view looking south from the top of Newry Hill

One particularly memorable piece was a boulder that was five feet long, by four feet wide, by two feet thick, with a seam of indicolite crystals running along the long side. Here we used the 16-pound sledge hammer to tenderize the boulder, followed by much pounding of chisels with our eight-pounder to convince the rock to split. We worked up a good sweat doing this in the hot afternoon sun, but came away happy with a dozen or so matrix pieces with crystals to eight inches in length.


The Dunton Quarry, now just an empty hole

As our energy began to flag, we took a break to walk around and see the sights - especially the famed Dunton Quarry, which lay only 100 yards to the southeast, just over one of the crests of Newry Hill. I felt disappointed at the sight of this gaping, empty hole. All the gem pockets had been systematically removed, of course, and when the search for more tourmaline had ended, there was nothing left but the towering 80 foot high rock walls of a big, empty quarry pit. Looking at the empty mine, there was absolutely no clue visible of the fabulous riches that had emerged from the Dunton Mine.


Collectors hunt for gem shards below the Dunton Quarry

Several hardy diggers were working the dumps just below the mine, in search of scraps of watermelon tourmaline. One collector showed me her prize find of the day: a tiny ¼" scrap of gemmy red and green tourmaline, her reward for a full day of digging and screening in the dumps. That kind of collecting is decidedly not my cup of tea; give me a 16-pound hammer and I'll be quite content with whatever I find!


The twin tunnels of the idle Nevel Quarry, on the north base of Newry Hill

We were scheduled to leave the mine by 3:45, so as the deadline approached, we backed the four-wheel drive truck right up to the area we had been working, and loaded several more full buckets plus four or five garden-rock size chunks directly into the back of the pickup. On our way out we took a short detour to see the famed twin tunnels of the Nevel Quarry. Further down, we stopped at the farmhouse to change out of our sticky, dirty work clothes, and then went over to thank Bob Brown, the retired logger and former Plumbago Mining security guard who lives on the property and oversees operations at the mine. Bob is an affable gentleman, reportedly nearing 90 years of age, but still as spry and sharp of mind as you could hope for at that age. I asked him if he ever allowed mineral clubs to come to Plumbago on field trips. His answer was positive, so I quickly arranged a date in mid-October for the club I belong to - the Keene NH Mineral Club - to come on a field trip.


Dick sits on a track drill used to sink holes into the pegmatite for later blasting

THE SECOND FIELD TRIP: OCTOBER 2011
It was less than two months later, but what a change Mother Nature had worked on the rolling hills of Central-Western Maine. The lush green deciduous tree leaves of high summer had been replaced by the oranges, yellows, and burnt umbers of mid-October colors. Though it was about two weeks past its peak, the foliage glowed in the bright fall sunlight. We were blessed with an Indian Summer day, with temperatures starting in the 30's but reaching the low 60's by mid-afternoon. Exactly 33 members of the Keene Club had converged on Newry for a field trip to this legendary, but long closed-to-collecting locality. Thanking our lucks stars, we once again made the bumpy trek up the long, tortuous dirt road that led to the Blue Pit workings atop Newry Hill. There we parked our trucks and people jumped out and headed in all directions to comb through the tailings.


Late fall foliage shines in the sun on Plumbago Mountain

The Blue Pit had undergone a few changes, too. It was deeper, more carefully cleaned out, and you could actually see the edges of the pegmatite core, an area which some heavy-duty investors had bet would hold more tourmaline. It was obvious that the mine had been worked hard since we were last here.


Between August and October, blasting and excavating had deepened the hole
considerably in the Blue Pit - but, unfortunately, no new pockets were opened

The area to the west of the pit had been graded with the big bulldozer, and all the loose tailings were spread out for convenient inspection and picking. Our group of excited rockhounds spread out in a flash, quickly picking up pieces of rock and turning them over and wiping them clean, searching for blue tourmaline. Excited cries rang out in the cool morning air as people exulted in their newfound discoveries. I could see happy, smiling faces all around, and it was clear that no one was going to go home empty handed.


Bob Brown drove up to the mine to see what we were finding, and to do a little digging himself…


Bob working with a hoe in the Blue Pit (I offered to help him out, but he just chuckled)

Dick and I did pretty much what we had done on our first visit, searching out promising looking chunks of rock, then beating them up to extract the tightly-held tourmaline treasures. The morning went by quickly, and after a lunch of made-on-the-spot peanut butter and strawberry jelly sandwiches, we continued digging in the warm afternoon sun.


A happy Keene Mineral Club member shows off his prize find: a 1" terminated indicolite crystal

We took frequent breaks as club members came up to show us their finds, showing them off or asking what they had turned up. In addition to blue tourmaline, we saw some green elbaite tourmaline crystals, lots of cleavelandite, spodumene crystals, brown lepidolite, childrenite, cookeite, montmorillanite, several nice discs of columbite in matrix, and more. I wandered over to one collector's car, an all-wheel drive Subaru, and looked in the back seat. To my astonishment, she had completely filled the foot wells in the back seat with her prize finds, and had then piled even more specimens on the back seat itself. I had to laugh. It was easy to overindulge, especially because the collecting was so easy, the quality of the material was so high, and the sheer abundance of good material was almost overwhelming.


An enthusiastic collector works to extract a blue tourmaline crystal from a large cleavelandite boulder (note the plethora of patches of blue tourmaline dotted across the entire surface of the rock)

Once again the 3:45 PM deadline came on us all too soon, and we had to scramble to load all our prize finds into the pickup for the long ride down the hill. Dick and I stopped at Bob Brown's house out by the road, where I purchased a specimen he had shown me on my first visit, and had held it for me until now. It was a 15 inch "sunburst" of dark blue tourmaline crystals, radiating out from a central point in the middle. The crystals were not gemmy, but their high luster, sharp habit, and intense inky blue color made this a very significant specimen from a true classic locality.


A spectacular 15" indicolite tourmaline radiating crystal "sunburst"
that was one of the trophy discoveries from the Blue Pit in 2011.


Close up of the center of the tourmaline sunburst; note how the blue-green coloring in the middle transitions to dark blue


MINE ACCESS AND FUTURE FIELD TRIPS
The Keene Mineral CLub is 2012 is hoping to make a return visit to the Blue Pit in Fall of 2012. And, 2012 is reportedly the last year that the Maine Geology Survey (MGS), with oversight by Woody Thompson and Duane Leavitt, will offer field trips to Newry. Field trip participants are selected using a lottery system. For details, visit the MGS website here:


http://www.maine.gov/doc/nrimc/mgs/explore/minerals/fieldtrips/fieldtrips.htm