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Table of Contents - Liz Fodi - Gary Glenn - László & Elsa Horváth - Tony Steede - Wm A. Henderson, Jr. Y2K at Mont Saint-Hilaire - László & Elsa Horváth No, Y2K in the title has nothing to do with the long- predicted disasters which were to throw us back into the Stone- age. It seems that we have all survived the change of the four digits quite well, and by the time collecting started in the spring of 2000, hardly anybody cared to remember or mention the famous buzzword. Now that we are in the new year, as well as the new century and millennium (the real one), it is time to review what happened in 2000 and more importantly what was found at everybody's favourite locality. Collecting started fairly early because of the record-setting mild weather and quarry operations resumed in early March. The first two blasts occurred on level 8 in the east corner, near the back ramp, in a rather interesting contact zone between nepheline syenite and sodalite syenite, and near the margin of the huge hornfels block. The zone was rich in marble xenoliths, igneous breccia and even had some small sodalite xenoliths, something we have not seen in many years. The second blast turned out to be one of the best that we can remember, providing nice big blocks of marble xenolith that collectors could nibble on for the rest of the year. The fresh blast also yielded blocks with pods consisting mostly of masses of peculiar altered pectolite crystals with analcime, calcite, sodalite and green amphiboles, and the richest find of UK61. The UK61 occurred as beautiful, vitreous, transparent, lemon yellow prismatic crystals up to 3 mm long, commonly forming hemispherical and "bow-tie" aggregates. Associated minerals included masses and veins of steacyite (the greatest concentration seen at MSH to date), monteregianite-(Y) as sunburst-like aggregates embedded in steacyite, a brown fibrous mineral resembling yofortierite, minor leucosphenite, mangan-neptunite, ancylite-(Ce), magnesio-arfvedsonite and many common species. The UK61 bearing blocks were almost immediately removed to clear the road and the ramp, whereas the bulk of this blast was still around in April. The marble xenolith blocks were very vuggy with excellent pectolite (up to 2 cm crystals), fluorapophyllite (up to 4 cm tabular crystals), lots of yellow prismatic vesuvianite crystals (up to ~2 cm), the best calcioburbankite, occurring as aggregates (up to 1 cm) of pale pink, short hexagonal prisms, as well as other rarities like stillwellite-(Ce), vinogradovite, mangan-neptunite, götzenite and hibschite. In April, the bulk of the rock pile was removed uncovering some marble xenolith blocks that would yield the find and the sensation of the year, sharp, lustrous crystals of deepest blue carletonite. The find occurred while we attended the Rochester Mineralogical Symposium and we did not witness the event, but we did see a portion of the specimens recovered. Essentially all the carletonite specimens were recovered by two local collectors and the Haineaults. A large portion of the specimens found by the two local collectors was fairly quickly dispersed, mostly in Europe, and photos and specimen descriptions appeared in German and French publications by mid summer. The carletonite from this find are mostly intergrown short prismatic crystals (cavity filling and cavity lining) 1-3 cm long, vitreous, translucent to opaque and a very striking, deep, inky blue. Very few specimens have more than a few intact crystals, but the colour is pretty amazing and the prices even more so. After all the excitement caused by the carletonite find, and the excellent collecting in the marble xenoliths, early summer was rather uneventful with some small but interesting finds of petersenite-(Ce) from a pegmatite vein on level 6 and some blocks of sodalite xenoliths from a blast also on level 6 with villiaumite and vuonnemite. These two minerals were really a welcome sight after so many years of absence. Collectors attending the field trips also reported the finding of quintinite, sabinaite, gobbinsite, horváthite-(Y) and UK32 (a new habit). During the summer the Poudrettes concentrated on their bread and butter, hornfels, resulting in rather slim pickings for most of the summer. In late summer, Gilles Haineault had arranged for some work to be done on the Poudrette pegmatite and the area around it. A few interesting veins were explored which yielded some rather interesting things such as neighborite (orange brown to almost black pseudocubic crystals), remondite-(Ce) (attractive sprays of white to pale grey, acicular crystals) epididymite (colourless prismatic crystals), eudidymite (stellate aggregates of pearly white platy crystals), beryllonite, brookite, dawsonite, corundum, hercynite, adamsite-(Y) and thomasclarkite-(Y). The most interesting mineral, however, turned out to be shomiokite-(Y), a rather elusive species which was known from a single specimen until this year. We spent most of September and early October in Europe and we were reassured on our return that not much was found in our absence. In October a large cavity in the N wall of level 9 (hornfels) was opened by Gilles Haineault, and later worked by other collectors, which yielded some very impressive smoky quartz crystal groups, some with an overgrowth of crude, pale pinkish fluorite crystals. In November, Gilles Haineault with help from the Horváths and Peter Tarassoff put on an exhibit of MSH minerals in the sugar house (sucrerie) owned by the Poudrettes at the foot of the mountain. This was the largest ever exhibit of MSH minerals with 24 cases (specially manufactured by Gilles for this event), representing some of the best specimens from the Haineault collection. The exhibit included two cases of MSH type minerals, two cases of rarities (mostly micros), one case each of MSH literature, faceted and polished MSH minerals, fluorescent minerals, rock types etc. The exhibits strongly emphasized the scientific value of the quarry and the natural history preservation aspects of mineral collecting to the local communities and their politicians, as well as to the Poudrette family. This was a very important public relations venture to convince the Poudrettes that mineral collecting has more than nuisance value, and to convey to the local communities that the quarry is more than an environmental blemish on the mountain. The exhibition, which was really excellent, was attended by about 500 people and may be repeated next year. An extra field trip coinciding with the exhibit was also arranged. Mid to late November proved to be very productive in the Poudrette pegmatite area as more work on the pegmatite resulted in the recovery of excellent specimens of adamsite-(Y) (sprays up to 2 cm), thomasclarkite-(Y) (spherical aggregates up to 1 cm), genthelvite (crystal groups up to 2 cm), shomiokite-(Y) (masses up to 2 cm), petersenite-(Ce) (superb terminated crystals up to 2 cm), elpidite (spherical aggregates of pale greenish crystals) and many other species including a number of yet unidentified minerals. The last blast of the year, in early November, occurred in a sodalite syenite zone on level 6. From a nice, fresh, pegmatite vein exposed by this blast excellent specimens of behoite, synchysite-(Ce), nenadkevichite, donnayite-(Y) and hilairite (all micro) were found. During the year the following species were added to the species list: niobokupletskite, adamsite-(Y) (both new species described in 2000), remondite-(La) (identified from material collected in 1998-99; new species described from the Khibina massif in 2000), korobitsynite (identified from older material at the Canadian Museum of Nature; new species described from the Lovozero massif in 1999), tumchaite (UK110; new species described from the Vuorijarvi massif, Kola Peninsula in 2000), manganocolumbite and vermiculite. In addition the valid species status of tetranatrolite was reaffirmed, so we can scratch gonnardite.  Good Fortune at Mont Saint-Hilaire 2000 - Tony Steede For one who only got to collect at Mont Saint-Hilaire twice last year, I got awfully lucky. Steve Szilard and I made the trek for the May trip, one that we particularly like to make as it has been the only trip in recent years in which collecting has been allowed for both days of the weekend. As experienced MSH collectors know, the quarry is always changing. In the previous year I had been able to find hibschite, tadzhikite, and a very small amount of datolite in a particular area of marble xenolith material. I was anxious to see if the area still existed. There was little left, and mostly barren. Instead, there was a boulder field, which included many large hunks of marble. Marble is the most difficult type of matrix in the quarry as it absorbs the sledgehammer blows and dissipates the force with little apparent effect. Nevertheless, the local collectors started to attack these megaliths with gusto. This strongly suggested that there were some good minerals to be found in them. Sure enough, they contained both carletonite and vesuvianite. The prize was quite large and attractive sprays of terminated vesuvianite crystals. However, it was still early on the Saturday and Steve and I knew that attacking one of these monsters too early in the trip would likely mean being less productive later on. Every time that I go to The Magic Mountain I try to find igneous breccia because of the interesting suite of minerals contained in that rock. There were several other boulder fields toward the North end of the quarry so we went investigating. As Steve and I clambered over the boulders I saw one rusty looking one that did not look very appealing but it was vuggy. It was a typical altered pegmatite like thousands of others that I had looked at without finding anything notable and I was not very impressed with its prospects. I probably would have ignored it except that I had the "persuader" conveniently available and Steve was nearby so I didn't even need to take out my loup. I knocked a chunk off and tossed it to Steve who looked at it and announced that it had some radiating things on it. Still not thinking very much about it, I collected some more. The radiating things turned out to be lemoynite, some of which were quite nicely terminated. Associated minerals are ancylite, zircon, synchysite, pyrite, and siderite, all on and between opaque feldspar blades. On the opposite side of the pile we found another boulder that had a large analcime sticking out of a vug. This was a fairly impressive chunk of nepheline syenite but nothing deters Steve so we attacked it. We each ended up with half of the boulder and proceeded to reduce it to smaller pieces that we could get in the van. The analcime was not worth keeping but there were other vugs in the boulder that looked more interesting. I kept one that contained a yellowish mineral that I assumed was in the donnayite family. When I got these home, I was initially perplexed. They were definitely not donnayite, so what were they? They were bright yellow and stacked so tightly it was difficult to determine the crystal shape. Not knowing what else to do, I hit it with short wave ultra violet light and was rewarded with a bright green glow. That narrowed the field, but quite a few minerals from MSH fluoresce green in short wave ultraviolet light. I then tried long wave UV and it still glowed bright green. That left only a couple of possibilities, so I went back to the microscope and was able to distinguish the hexagonal outline of the stacked willemite crystals. These are very attractive but were contained in only one small vug. On the Sunday, with no idea how fortunate we had been, we went back to the area of the marble boulders. Most of them seemed to be intact and there weren't nearly as many eager sledgers. Still not prepared to waste the rest of the day by attacking the marble, I found another large boulder, which was clearly from a contact between the nepheline syenite and hornfels. The interesting thing about it was that the contact was almost pure white and there were long clear crystals visible in it. In addition, in the middle of the nepheline syenite side there was a small patch of very dark amphibole or pyroxene in which there were some intriguing red radiating crystals. The boulder was about the size of Steve's van, so getting it back to Toronto intact was out of the question. The dark patch was right in the middle of this monster but I was able to extract some of it as well as the white hornfels. The red sprays turned out to be small clusters of sérandite. I had hoped that the clear prisms in the hornfels would be beryl, but am convinced that they are just very long crystals of apatite. However, this material contains some very attractive blocky crystals of rutile and a very few anatase crystals. Before the end of the day I did some work on the marble and was rewarded with a lovely spray of yellow-green vesuvianite crystals. Our next visit was the August trip. Once again I accompanied Steve in his van. On the way down the ramp I spied an interesting boulder in an area in which they had been piled. From the van it looked like a piece of igneous breccia. Steve obligingly stomped on the brakes and I was out of the van in a shot. Well, I was disappointed. It wasn't the wonderfully vuggy igneous breccia that it first appeared to be. Instead, it was another rusty altered pegmatite. Furthermore, I could see a fair amount of natrolite and most of the rock was sodalite syenite. I guess that I have become quite prejudiced. I don't like sodalite syenite and I don't like pegmatites with abundant natrolite. Nevertheless, it was a contact and it was vuggy. Those I like. Furthermore, I could see what looked like small mica books in it. Most of the vuggy stuff ended up in the van and we continued down the ramp. The rest of the day was spent working near where the Poudrette pegmatite had been. There are some interesting vugs in both the outer part of the pegmatite and the hornfels that are right beside the pegmatite. Other collectors were splitting open loose chunks of hornfels looking for sprays of elpidite and plates of eudidymite. I ended up attacking the hornfels in situ and found several lovely white sprays the likes of which I had never seen from the hornfels. A group of true MSH experts were gathered around (László and Elsa Horváth, Peter Tarassoff, Gilles Haineault, and others) and I was told that the white spray was the elpidite that others were looking for, together with the associated plates of eudidymite. After cleaning this material up, I discovered other interesting minerals. One is in the form of frosted clear to white (some slightly bluish) balls and blobs, which turned out to be strontianite. Another is represented by sharp crystals of yellowish or brownish orange, translucent, with adamantine lustre. I have difficulty describing the forms but they look somewhat like slightly twisted zircons with extra pyramidal faces. All seem to be growing on needles of a dark mineral. These turned out to be monazite, in a form and colour that I had not seen before. Associated with the above minerals is a red to brown mineral that has the shape of gmelinite but is probably altering to something else. Some crystals have a fibrous look to them. Before the end of the day I picked up a few pieces of rock that likely came from the Poudrette pegmatite. It is clearly pegmatitic and once contained fairly large blobs of eudialyte, most of which is now gone. An alteration product, consisting mostly of calcite, both as an opaque earthy coating and some tiny crystals, has been left. Within this material are two types of plates. One is tiny, a simple thin rectangular frosted plate. The other is clear and deeply striated vertically, with flat terminal faces, top and bottom, which infrequently combine attractively, to form what I call "Maltese" crosses. These are probably not truly platy, the striations being re-entrant angles. They can be found with UV light, do not effervesce in acid, and seem to be infusible. Much of what looked like the same altered eudialyte material was available in the same area in 1999 but I did not find any of these plates in that material. The micaceous plates that were collected from the boulder on the way down the ramp during the August trip, were identified by Dr. Andy McDonald of Laurentian University as caresite-3T. He also identified the lemoynite and the monazite, while both he and Malcolm Back of the Royal Ontario Museum identified the strontianite. I most sincerely thank both Andy and Malcolm for their help in identifying these minerals. I enjoy trying to do my own identifications but MSH is so complex that without the help of people like these, many of us would have more unknowns than identified species. The late, great Neal Yedlin used to end his articles on micromounting by saying "Buy and use a good mineral book." Very sound advice. My advice to Mont. Saint-Hilaire micromounters would be, forget your prejudices; if it's vuggy, take it home. Hilaire sabinaite fizzes NOT - Wm A. Henderson, Jr. On the September trip to Mont Saint-Hilaire, I collected what appeared to be sabinaite in mottled grey and white rock in or near the corner pegmatite. It occurred with light tan siderite, analcime, aegirine and albite. The crystals were transparent, colourless to light orange or pink, tabular (almost micaceous), hexagonal or pseudohexagonal, and 1-2 mm in size. The optics of the material fit sabinaite well. This, and the fact that the unknown looked like sabinaite collected before, made it almost a sure thing that the unknown was, in fact, very attractive sabinaite. There was one worrisome point, however. Mandarino's Monteregian Treasures reports that sabinaite "dissolves readily with effervescence in warm HCL." The qualifier "warm" is to be expected, since sabinaite is an oxide / carbonate, which will react much slower than a pure carbonate. When I tried warm to hot 1:4 HCL, and even warm concentrated HCL, I could see no reaction. Now Chao and Jiexiang1, in their paper on Hilaire sabinaite, did not mention acid tests at all. It is only the original paper on franconite from the Francon Quarry, by Jambor, Sturman and Weatherly2, which says sabinaite is "unreactive in cold acids but is soluble with effervescence in warm HCL." I mentioned this to Peter Tarassoff, and he pointed out that the Francon material occurred only as WHITE POWDERY COATINGS! As he and I are well aware, powdery coatings, like finely ground minerals have higher surface areas, and thus react with acids much faster than larger crystals or crystal fragments. When I ground some of my unknown from Hilaire and warmed it nearly to boiling in concentrated HCL, I finally saw some of the fragments begin to rise instead of sink in the acid, a sign that tiny attached bubbles were helping them float. Only under my microscope could I see the barely visible bubbles of CO2. At last, a faintly positive test for a carbonate! There are several take-home messages from this story, as follows:
2 Jambor, J.L., Sturman, B.D., Weatherly, G.C. (1980) Sabinaite, a new anhydrous zirconium bearing carbonate mineral from Montréal Island Québec. Can. Min., 18, 25.
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