@
BLACK TUSK QUARTZ
Garibaldi Peak (Black Tusk) - Whistler, British Columbia, Canada
The following is my article as it appeared in the B.C. Rockhounder - Volume 10 - 2007
Black Tusk Quartz from Whistler, British Columbia, Canada.
This article is about a recent discovery of Quartz found just south of Whistler, British Columbia, Canada. It was made in the fall of 2005 during one of my work trips as a forestry engineer exploring old road systems in an effort to locate timber for development. In my job, I am fortunate to have a chance to drive many old and new mountainous logging roads through some very rugged terrain. Having been a rock hound from a very young age, I am always on the look out for interesting rock formations in the cut banks of the roads I drive. I stop every time at the first sign of white bands of quartz in the country host rock. Always it turns out to be either massive lenses of quartz with little to no cavities, much less crystallization; or very coarse and loosely held together material that crumbles at the touch. I had resigned myself to the knowledge that I would never find any interesting mineralization on any of my drives; the road building crew or some other road user would have found it long ago. Finding minerals wasnft supposed to be that easy. I had read the works of John Sinkankas and always been inspired to collect minerals in the field. I had been on forays to old mines and known localities with the local rock club, but of course, such areas were already heavily exploited and the quality of material was always of interest, but not sufficient for display in a top quality collection. I had been to the old defunct Keystone Mine in the Coquihala pass; a bit of small quartz druze and some massive galena/sphalerite. I had been to two local quartz localities and found a nice small point in the refuse of one and not bothered to bring anything home from the second. I had been fortunate enough to find an eroded garnet in a piece of some schist while working in Ruby Creek (the old timers at first thought the garnets they were panning in the mouth of the creek were rubies, and hence they named it as such). Nice but of only passing interest to the serious collector of fine specimens. Then one day in the fall of 2005, while driving a full truck with our crew through some sinuous logging roads just south of Whistler things were about to change. We had been sent to do an inspection of an old deactivated road system that was planned for re-activation. It was raining very hard and we were not happy about having to be in the field that day. Very early on I had found a small boulder of quartz by the road. I had noticed it looked like it had some cavities and had broken it open with the head of my axe. I found a small plate of some 2cm high milky white quartzes. I had been fairly excited about it as it had been the best thing I had ever found up to that point – however it was still nothing special by most peoples standards and nothing I would have displayed in my cabinets. By the time two ofclock came around, I was fully back into work mode and not thinking rocks anymore. It had finally stopped raining and we were in better spirits and back in the truck driving to a new area. We were driving up steep roads and through many water bars. The driving was slow for these reasons, which always gives you a chance to look around you. I had noticed some quartz stringers in the cut slope, but they looked very red from hematite. This usually means that they are heavily fractured as the red stain works its way into the cracks in the quartz thereby giving it a rusty look. This type of quartz is never recoverable, even if you are lucky enough to find some crystals, so I didnft even bother to stop. We drove on for another 5-10 minutes when we drove by a big rock face on the edge of the road. We were moving faster so I didnft get a close look by I did spy a 30cm band of quartz running horizontal to the ground and I did look like there was some cavities in it. Interesting I thought. I knew I would be driving back this way as I was near the back end of the road system so I kept driving. Finally we hit the last road and turned around. Luke, one of my crew members whom I had subverted into the wicked ways of rock hounding had noticed the band as well and just before we came around the corner to the place where the seam was, he asked me to pull over up ahead as he had seen something of interest. I looked over my shoulder at him and assured him that I had already intended to stop before he even asked. We exchanged a few comments about how promising it had looked. As soon as we pulled up to the rock face, Luke and I were out of the truck so fast the other two were still un-buckling while we had begun to carefully inspect the face. There were definitely some vugs in this seam! We could see some crystals poking out from the roof. They looked like they would require some heavy work to remove but they were about an inch long and very clear. I could feel my heart pounding and could tell Luke was excited as well. We had talked about finding something like this one day, and now it had happened. By this time, the other two crewmen had come out of the truck and seeing what we were doing, began to look around. Luke and I heard a shout and when we turned around one of them was standing there holding a 3h point in his hand. I was milky but had a high luster to it. We couldnft believe it and rushed over there too look at it in his hand. I was chipped on the tip and had some very faint traces of some blackish looking inclusions on one side but it was by far the biggest and nicest thing I had every been part of finding. He had found it lying in the grass by the edge of the road. We quickly all scanned the area and within 5 minutes had found 4 more. It was at this point that I realized we had found something worthwhile, not just of local interest, but quality that was good enough to display in a cabinet. I was very excited and didnft know what to do next - keep looking in the ground or go back to inspecting the vugs! Luke began to inspect the pockets and I kept looking near where the big points had been found. It quickly became obvious that the road building crew had dug up part of some of the pockets and used it for road fill. Large chunks of quartz and crystals were all over the edge of the road. I couldnft quite believe it at first. How could they have missed it? I was picking up shards from the pocket. It became quickly obvious that the pocked had seen seismic activity during its genesis as much of the crystals were healed giving them that euhedral look, that is all faces are terminated and with complex multi-faceted faces. I had picked up about 10 of them when Luke called me over. He had his arm elbow deep into a pocket and was pulling out some strange blackish green mud. At sparkled a bit but was other wise not inspiring. He handed me the mud and said to squeeze it. I did and quickly found it to be covering something. It was thick and hard to clean off anything but one face, but there it was, a crystal! I shouted to keep going and he proceeded to empty the pocket of mud for 10 minutes. I would take the handfuls and place them on the hood of our truck. By this time, the other two crewmen were scraping around and pulling some decent points out of the road fill. We continued to dig for another 15 minutes when I realized I had better put a stop to it as it was getting late and we had a long drive, and more importantly, I didnft want anything damaged as we had no proper tools and were using old axe heads to chip away at the rock. It took a bit of doing, but I finally pried them away from the face and we got back in the truck and headed for home. I sat in the back and was of course inspecting some of our mud encrusted crystals. Some of the mud had dried while laying on the hood and it became less mud like and more dust like. Once dry you could easily remove it with your fingers. The more I cleaned off the mud the more excited I got. The crystals in the mud were doubly-terminated and damage free! About 5 of them were perfectly shaped eherkimer diamondsf after the famous quartzes from Herkimer Co. NY, USA. These 5 also had the faintest of purple color to them; just barely noticeable and two slight to call Amethyst, but definitely noticeable in the right light. Some of the mud didnft seem to come off no matter how hard I rubbed it. It appeared to be included in the outer layer of the quartz giving some a complete coating of this black green sparkly mineral we couldnft identify. We also managed to find some nice rhombohedrons of calcite that had been slightly etched. Not clear but still interesting to find. Lukes hands were sliced up from empting the pocket and all the cuts were engrained with clay. He was hurting but you couldnft have removed the smile from his face if you tried. Me too. All I could think about during the 3 hour drive home was when I could get back there again. By the time we had gotten home, Luke and I already had a plan to re-visit the location the coming weekend. After a few sleepless nights waiting for Saturday to arrive and a 5am wake up call we met and proceeded to drive up there. Armed with tools, my Sinkankas books, and a plan to do things methodically we pulled up to the location. Before we had left the last time we had rolled an old log over the area and tried to make it look undisturbed to the casual observer. It didnft look any different so we both sighed in relief and proceeded to clear away the obstructing material. I donft remember the details of that second visit as well as that magical first day, but I do know we proceeded to find crystals all day and came home with some nice pieces. Sure there was B grade stuff as well but with the coating of clay over it, you could never really tell for sure how good it was until you got it home started to clean it up. We managed to get up there one more time before the snow came; we found some more, but the easy stuff was all gone and the pickings slimmer now. I waited for winter to pass which gave me some time to do some serious cleaning of the material. The more I cleaned it, the more I began to realize that we had found something very special. I sent some of the mud to UBC to be analyzed and found it to be chlorite. The way it coated some of the specimen, while at first thought of as a nuisance, was just spectacular and really set this location apart from the typical clear white quartz you find in Arkansas or Brazil. Upon doing some research about this association, it came to my attention that it closely resembled some of the great finds of quartz in the European Alps. No smokey quartz was present, but the growth patterns and the chlorite dusting were almost identical in many respects. We had also found a coating of some small clear tabular crystals on some of the specimens. It was also identified and was found to be Albite; interesting but too small for display. After a particularly long and cold winter, with a very large snow pack to deal with, the site finally became accessible again. I had decided to bring my father Lloyd with me as it was his 70th birthday and I knew he would appreciate it. You can drive right to the site so access for his somewhat limited mobility wouldnft be a problem. We investigated the face for a while but came to the conclusion that there wasnft much left of the original find to continue there so we drove around the immediate area looking for more sites. We drove around for 20 minutes without finding anything. On the way back to the original site, just on the other side of the hill, I saw some white poking out of the moss. I got out of the truck while my father waited and proceeded to poke around. I did find some massive quartz, but no crystals were apparent. I was just about to leave when I decided to stop and enjoy the view before I left. As I was standing there, I noticed at my feet a 3h clear crystal poking out through the carpet of needles! I yelled to my dad in the truck who got out and yelled back at me what was wrong. I only had to pick up the point and waive it in the air to get him scrambling through the brush (as good as a 70 year old can scramble!) to the base of the hill where I was positioned. We then proceeded to start removing the layer of moss and needles covering the talus slope that we were perched on. Within minutes we had located a zone rich in the chlorite clay. After cleaning it up, we found a large pocked that was already opened up from the top through which we could reach down and pull out big clusters of chlorite clay encrusted crystals. The morphology of this vug was a bit different; there was more etching of the quartz and the chlorite was much darker and sparkly. The vug had also experienced more breakage and subsequent re-crystallization. It also produced a few of the only scepters from the whole find. Needless to say it was a birthday my father wonft soon forget. We pulled out some of the top specimens from the pocket, including the two large undamaged plates and several other unique pieces. My father had been collecting minerals since he was a young man but this was the first time he had ever had a chance to clean out a pocket of real top quality items. A nice birthday present for sure. Ever after this pocket was known as the 70th Birthday Pocket. This area also produced some very nice plates of clear quartz – that is with no chlorite present anywhere. That about sums up the history of how the find was discovered. I will now try to relate to the best of my ability – I am no geologist – the paragenesis of the find.
Pocket Creation
Chlorite is an Iron Aluminum Magnesium Silicate Hydroxide. These Quartz crystals were originally formed in a pocket rich in Silicon Dioxide solution. Later intrusion by a Chloride bearing solution (a product of low-temperature retrograde metamorphism and possibly also of corrosive meteoric water) occurred in many pockets as a dark green, fine-grained clay. This Chlorite clay caused much of the quartz to become dulled and rounded by chemical dissolution. After the chlorite clay was deposited, continued (but limited) growth of the quartz in Silicate rich solutions continued to occur, resulting in an inclusion imparting a greenish-black color to Quartz. Chlorite-group minerals also occur as components of muddy pocket residues. Pockets with "Chloritic Quartz" typically contain Epidote that has been chemical dissolved, suggesting that the corrosion of the Epidote may have contributed to the formation of Chlorite. This is probably the case in these pockets as minute pockets containing fully formed Epidote were located only 150m away. This is further supported by the fact that crystals that were hanging on the top of the pockets were un-included with chlorite. Some time after the chlorite clay was deposited a final mineralization occurred where a very thin reddish film of hematite was found to be covering both the clear and chlorite clay in some zones of the pocket. This hematite effectively armored most of the soft chlorite clay on top of the quartz and did an excellent job of protecting the crystals and is one of the reason so many specimens survived the original road building efforts that unearthed the pocket.
Crystals Formations
Pretty much every form of quartz crystallization was evident in the pockets. The only form not found was the rare form of Japanese Law twins (called Japanese as this is the first location it was documented from). Tabular, double terminated, euhedral, scepters, and regular points and clusters. They were all there. The most impressive were the double terminated crystals. Also known as efloaterf crystals, these are crystals that have formed within the Chlorite clays found within the pocket. Most likely broken off the cavity wall during some stage of crystallization, these crystals continued to grow and the broken ends became terminated or, re-healed. As a result, they have no point of attachment. Also, present was one example of a efadenf style pocket crystal which probably formed from continued fracturing and re-healing. These are terminated on all sides and are also known as eeuhedralf. The degree to which the chlorite was present in the quartz was what really set this site apart from most others. Numerous examples of this interesting association; ranging from fully included and coated crystals to minimally included tips and barren quartz added to the variety. Below is a list of all the minerals that were noted at this location, however, it would not surprise me if more were found upon proper chemical analysis.
Quartz -(Silicon Dioxide - SiO 2)
Chlorite -(Iron Aluminum Magnesium Silicate Hydroxide - (Fe, Mg, Al)6(Si,Al)4O10(OH)8)
Albite -(Sodium Aluminum Silicate – NaAlSi3O8)
Calcite -(Calcium Carbonate - CaCO3)
Epidote -(Calcium Aluminum Iron Silicate Hydroxide – Ca2(AlFe)3(SiO4)3OH)
Hematite -(Iron Oxide –Fe2O3)
Conclusion
A find like this is a very rare event; most people can go their whole life hoping to find such an occurrence with no luck. I know how lucky I was and hope to be again someday. I am very proud of the find and am always happy to display the crystals to anybody who is interested in such things. I recently had the pleasure of being able to display them at the 2007 Annual B.C. Gem and Mineral Show in Abbotsford (my home town) where many people with interest in such marvels of nature were able to enjoy them. I received a lot of comments and interest in the locality was definitely there. I hope to be able to display them again one day, and maybe with some new items if I can manage to make another find. I hope the story of how these specimens came to be was helpful and interesting to the reader.
@
Black Tusk Mineral Specimens for Sale
@
@