|Mining Operations at Mount Mica & Orchard Pit Mines, Oxford County, Maine.|
Coromoto Minerals Mining
Operations at Mount Mica,
October, November, December 2007
Our mining around pocket 6 and 7 revealed many small vugs containing tourmaline and quartz very similar to the material from 6 and 7. Each space had to be thoroughly investigated and its contents recovered. This process was time consuming and cut down considerably on 'tonnage'. After nearly two weeks of 'mopping up' and expanding the advance across the face we were ready to press on. In the image to right, the back wall of pocket 6 is visible high above the buckets near the ceiling. Our subsequent advance is to left. The current advance can be seen to the far left in the background of the image.
The next advance of the drift produced no pockets but the feldspar was showing the striped fabric that indicated pockets were around somewhere. It was also becoming increasingly clear that we were now mining the down side of a plunge. This complicated blasting as the pocket horizon was trending diagonally across our working face. There was no obvious 'safe zone' for blasting. We almost always drill into a pocket before it is exposed by blasting. When we don't, our practice is to blast either above or below the presumed location of the pocket zone hoping to 'peel' into something. In this way we spare small spaces that are not revealed during drilling. We have learned that different regions have their own particular 'no brainer 'pocket indicators. In this area the striped spar ( colored by possible lepidolite up take ) is a strong indicator. This microcline usually lies below the pocket. We also look for the spar to turn blocky. In this textural feature lies above the pocket. Curved rusty cracks that seem to be arranged around a common locus, like an onion, are indicative of a large space. In the image, the blocky texture of the microcline can be seen along with its ascent towards the right. The green line denoting the pocket horizon overlays this microcline. Finer textures are visible above and below this spar. The start of our latest advance is on the left. Based on appearance alone, we felt we were approaching a promising area.
Our guess proved to be accurate as we soon drilled into a space. In the image above, the space sits immediately behind the dark stained area that is probably lepidolite. A closeup shows how the microcline coarsens near the pocket. Once we had chiseled into the pocket we saw that microcline formed its roof and had broken into many angular pieces. These microcline 'tiles' filled the upper portion of the pocket. Once we had cleared some of this material, more interesting crystals began to appear. The first was a large smoky quartz. It to be appeared oriented point down in the debris. At first only the stem was visible. We had no idea what it would amount to when excavated. We extracted it to find to our surprise it was a huge scepter quartz (60cm). On the stem of the scepter there was a mat of small blue tourmaline that graded to colorless near the pinacoid which in itself was red. We have learned from experience that, if a pocket has tourmaline, the color pattern of the first piece found will be a very good indicator of almost every other piece regardless of size. This was indeed an interesting combination and most probably a harbinger of what we might possibly find.
As we probed further into the pocket we began to find many small (2cm) tourmalines identical to those on the scepter quartz. As usual with polychrome tourmaline at Mount Mica, entropy exerted it's heavy hand. Any larger tourmaline that may have developed within the pocket were broken into a jumble of pieces. Over an hour or so we found about 200 small tourmalines all cut from the same mold as the one in the image. As we worked, we beseeched the Rock Gods to bestow upon us a just one or two thumb sized specimens manufactured to the same plans as the small crystals. Our pleadings fell upon deaf ears. Not to engage too much in the mystical, I have noticed that when we gift away a small part of the largess of Mount Mica ,the RGs seem to notice and approve. Jokingly (but only somewhat), I handed a small tourmaline, like the one in the picture, to a visitor. I explained how the 'Rock Gods' seemed to be appreciative such small gestures. Seldom does a visitor leave Mount Mica without some small token as a gift and it is much more cost effective than Stonehenge. SO...as we continued to dig and wash the pocket, it eventually developed into a soupy opaque clay filled bowl. Large pieces of microcline had fallen into the pocket over the eons and were now suctioned fast in the wet the clay. One by one we pried these pieces out with a 'mongo' bar. Reaching into soup, I could feel another microcline. Without a great deal of thought I placed the bar under it and levered it up. What happened next astounded us all. A huge tourmaline, modeled after the many inch long crystals, lurched out of the soup, termination first, like the bow of Trident submarine erupting the surface. After the comotion subsided, all hands castigated me for using a pry bar to extract this piece.
Digging a little more we found another section and then another. Three pieces comprised this beauty. On close inspection of the pocket roof we could see where, at one time, both the large quartz scepter and the tourmaline had been attached. The tourmaline had apparently begun growth as schorl and developed its color within the pocket. Interestingly, the break near the end of the crystal began to develop a flat termination through re-growth. The other side of the break remained lustrous with no apparent further development. Both pieces were found in the pocket within inches of each other. There appears to be some gem potential in the crystal. The section on the right is a peach red color when illuminated from the side.
In the image above showing the crystal sitting in front of the pocket beside a chisel, a microcline is visible to the right in the background. This microcline crystal proved to be one of the better pocket microclines we have found at Mount Mica. Notice the small blue tourmaline crystals that have grown on one of the faces. (See image to the right)
As we continued to expand the advance to the west (left) we opened another small face that produced one decent tourmaline section of gem quality. This section produced a very attractive blue-green stone of about 3 carats. Our hopes were high that we would find more of this particular shade of material. It did not happen. As we worked this area we could see that the feldspars were indicating promise. By then we were into November. Our plan, as discussed on other pages, was to leave a substantial pillar to support the roof. We set aside about a 6m square of pegmatite for this purpose. At this point we decided to work the pegmatite just to the west of the pillar and in a southerly direction. Though the mineralization looked promising, the steep dip made working the pegmatite difficult.
After struggling with the steeply dipping section, we again turned our attention to the up dip side that produced the big elbaite shown above and now dubbed 'Fuji'. Just to the north of the Fuji pocket we detected another pocket area. There we drilled into a small space. Using the blowpipe, we were able to extract a few small light green 'matchsticks' that graded to red tips. Our hopes built that when we opened the pocket we might find a few green thumb sized crystals displaying this color combination. Unfortunately, this was not to be. There were a few small gem sections recovered but nothing in the digit class... thumb sized or any other appendage for that matter. Though this pocket did not pan out as hoped, the area continued to look promising. Several spots on the wall
trickled water, so we convinced ourselves more was ahead of. It just required a little tonnage...as always does.
The small green matchsticks pictured above resembled some of the watercolors Hamlin made of crystals found in the 'New Pit' and illustrated in his book 'The History of Mount Mica'. Though I possess an original, I frequently consult my reprint of this work produced by Rubellite Press. These resembled plate XLII depicting crystals found in November of 1893.We were indeed working within the pegmatite just below the New Pit. Perusing Hamlin's illustrations I could see none reminiscent of Fuji. This was an interesting area to mine but I was constantly troubled by the notion that .though the pickings were, good, the future in this direction was limited. Mining further north we would break to the outside. Although substantial pegmatite lay between us and the main pit going westward, this too was an exhaustible heading. As difficult going as it was, I much preferred mining eastward where no limit has been established. Some observers believe that the pegmatite in that direction will change chemical composition, or at least segregation, such that, though it will still be Mount Mica, its beautiful crystal creations will be exhausted. I don't think so. We hope to prove it on our watch at Mount Mica.