After seeing the aquamarine display at the SNRA headquarters on a ski trip I was determined to mount an expedition which would no doubt make me rich!. The first step in planning any prospecting trip is to learn all you can about the area you are visiting and the deposit(s) that contain the treasure. I started by checking my copy of John Beckworth’s Gem Minerals of Idaho. That mentioned a discovery of aquamarine near Atlanta Idaho and a possible occurrence up Sheep Creek a tributary of the Middle Fork of the Boise River. I also ordered a copy of Prospecting for Beryllium in Idaho Idaho, Bureau of Mines and Geology Information Circular 7. I went down to Semantics which was a mineral shop in Seattle. Casey had heard that they were finding some cool stuff in the Sawtooth mountains. Lanny Ream’s name came up in the conversation as an authority on the subject. I gave Lanny a call and he was most helpful. The big choice was to come in from the Stanley (east side) and hunt there or come in via Atlanta and the Middle Fork Boise River trail. This last was a considerably longer hike but was a known area to produce aquamarine and topaz over a large area around Glens Peak as per the info circular. I decided on the Middle Fork route mostly due to the adage that you find stuff where stuff has been found before. The trail in looked a lot easier than most Cascade hiking of similar length. The general consensus from collectors I talked to was that the tool required for this trip was only a long handled screwdriver to clean the pockets. This is because the aquamarine is found in a pink granite of the Tertiary age Sawtooth Batholith. This rock is host to miarolitic cavities as well as pegmatite pods of varying sizes. For more information see Idaho Minerals by Lanny Ream or the info circular. . Prospecting involves searching rock exposures for cavities and using the screwdriver to pry out any crystals/plates. For more information see Idaho Minerals by Lanny Ream. I couldn’t bear to not bring my rock hammer and was later glad I did. I enlisted my long time hiking buddy Barry (not a rockhound) by promising riches beyond his wildest dreams and some good fly fishing. We decided to go in mid July or as soon as the snow was gone. We selected Spangle Lake as our base camp because it was near Glens Peak which was identified as the center of an area of aquamarine concentrations. We decided we would make the trip in two days. We took our traditional frozen steak and potatoes for our first night feast. We also made sure we had plenty of snake bite medicine (Jack Daniels) in case of any trouble or celebration. Finally the report from the ranger station was that the trail was generally clear. We waited another week and then we were off!
The trail was in good shape, the river was pretty and not too high and the fish cooperative the first night. Per custom we feasted on steak that night but they were so good for breakfast! As we hit the trail in the morning we were passed by an older couple and their grown daughter. We thought nothing of it but they will play into this story later. The second day as we hiked up the rise directly to the south of Little Spangle Lake we found our first sign of mineralization. This was an area with a lot of very small (<.5 inch) miarolitic cavities (vugs). They were all lined with tiny smoky quartz crystals. We did a quick reconnoiter with our packs still on but did not find any larger cavities nor did we see any sign of any aquamarine. After three trips experience I am sorry we did not prospect this area more extensively. There may have been zones with larger cavities. However we were in a hurry to get to the “good stuff”. We found a nice campsite at the lake but the fish were not very cooperative with the flies we had available and that persisted the whole trip. We ended up hiking to other lakes for most of our fish. The next problem was the mosquitoes. Yikes they were thick and hungry! Our 100 percent DEET bug lotion discouraged many but not enough. This was the first lesson. Don’t come in early summer. My next two trips were the first week in September and they were bug free. The good news was that the sunset on the pink granite of the batholith on Glens Peak was completely awesome and we had an ample supply of snakebite medicine which helped make the skeeters more bearable. That night we plotted our first day’s prospecting route which we decided would be a traverse of the north face of Glens peak.
The next morning, after a nice trout breakfast, we began hiking Glen’s peak from the the trail pass down to Ardeth Lake. We climbed about 350 - 500 feet above the pass elevation for the traverse. Don’t hold me to that estimate it was a while ago. There was a fairly large talus slope which we hoped would have a relatively stable zone to traverse and sample the rocks from higher up the mountain. We had not gone far before we found our first exposure of aquamarine on the divide. In these mountains aquamarine sometimes forms joint fillings in the rock. When lying horizontally and exposed by glaciation the aquamarine forms a sheet on the surface of the rock. We picked up a chip or two but the sheet was completely impervious to my rock hammer and screwdriver. A bit further up the ridge we found another exposure. This one appeared to be more of a mini-pegmatite because there were the ends of small pink feldspar crystals visible in places in the blue. The “vein” was pretty vertical. I decided I really needed a sample of that so I pounded with the pick and levered with the screwdriver and finally managed to free a small specimen displaying the pink and blue. It was obvious somebody had been there before us because there was no float or chips lying loose. We continued on our chosen route periodically finding small vugs with very small smokey crystals of .5 inch or less. We found one larger one which had been cleaned. No sign of aquamarine crystals. Our crossing of the talus slide was foolish and scary. We saw no trace of aquamarine in the slide. There were not any sizable vugs either. We elected to not make another traverse so we ate lunch and studied the map. Barry went to relieve himself and next thing he is hollering come over here. I wander over and he is standing next to a talus block about 15 feet high and 10 feet across. The pink granite has a 3 foot diameter blue aquamarine sunburst on the side of it. It is totally stunning and the aquamarine is deep blue. I cursed our decision to save weight by leaving the camera at home. We spent over an hour hunting the vicinity for vugs with no luck. We worked our way down slope and eventually back to camp without finding anything but small crystals of smokey. There were not many vugs in this area nor any more sign of aquamarine. All in all it was an excellent day and surely the big strike was just around the corner.
The next day we decided to focus on trout fishing so we hiked back down the trail to the series of lakes starting with Little Spangle Lake and ending with Rockslide Lake. We elected to fish on the generally SW side of the lakes. Little Spangle lake had good fishing for 10-13 inch cuts. We way overspent our time budget at Lake Ingeborg trying to catch the giant trout that were submarining around in the depths. While Barry was madly switching flies I managed to find a clear .75 inch topaz crystal perched in the remains of a cavity on a little bit of a ledge. In general this area did not have any great concentration of cavities. We found more small smokey crystals but in general we were still waiting for the big one. At Rock Slide lake we caught and released a few fish but no big ones. We ran into a couple guys on horseback who said they had been fishing at Three Island Lake. They said they had good luck with Cutt’s up to 23 inches long. I have a gut feel about that area which is a drainage on the Northeast side of Plummer Peak. If I went back I would really like to prospect there and the area up towards Low Pass Lake which is directly above the area I found the topaz. At any rate we hiked northwest of the trail climbing most directly (as possible) back to base from Lake Ingeborg. We found no vugs at all on this route. Our spirits were a bit down and so we dosed ourselves liberally with snakebite medicine. We also managed to get caught in a thunderstorm but we had a safe campsite and the tent was dry.
For our third day’s activity we decided to hike back up to the pass to Ardeth Lake and prospect the other direction from the first day. We went mostly to the north west of the pass. skirting below the talus slope. We did find a pegmatite lens exposed by glaciation with large quartz crystals frozen in it. There was no sign of any pockets and we didn’t have any decent tools to excavate the soil around the pegmatite so we continued on our way. We managed to work our way over to the unnamed high lake directly east of Ardeth Lake. We found some cleaned out vugs after passing below the talus slope to the east of the pass. We hunted all day and didn’t find a trace of aquamarine. After this very disappointing day we decided to cut out a day early and go over to Dismal Swamp and screen for topaz. That will not be covered here.
After breaking camp we hiked the 16 miles or so back down to Atlanta. We arrived about 5 PM and went to the local watering hole and ordered beer and steak and baked potatoes. It was a simple but awesome meal. The bartender was kind enough to give us directions to the hot springs which run out of a bank near town and into the Boise River. We bought some beer to go and went over to the hot springs, which we had to ourselves. The water was about 100 degrees and the pool constructed was about 3-4 feet deep. It was great! We sat in the pool and decided that even though we weren't rich we had had a great time. As it got dark and the stars came out the hot water just melted us into puddles of bliss.
After the side trip to Dismal Swamp we went to Boise and stopped in a rock shop. I can’t exactly remember the name but I think it was Stewart’s House of Gems. Low and behold working in the shop was the man and his daughter we had met on the trail. We told them we had been hunting gems and hadn’t done very well. He went in the back and came out with three gemmy aquamarine crystals. The largest was the size of my index finder and the smallest was about an inch long and maybe .25 inche in diameters. We asked where they were hunting and they said the Camp Lake area which was on the other side of Glens peak from our camp. That was all I needed I swore I would be back next year when I had more vacation and this time I would be rich!!!
Author
Topic: Sawtooth Aquamarine Hunting - Trip 1 (Read 10381 times)