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Fluorescent Mineral Collecting Field Trip to the Midwest

In early September 2018, after it looked like my grandchildren’s parents were required to prepare for a U.S. Government shutdown on the first of October, I cancelled my plans to take the grandchildren to the fall Franklin Mineral Show (from September 29-30, 2018). As a Plan B, I decided to go to the Midwest Chapter of the Fluorescent Mineral Society (FMS) meeting and fieldtrips near Cave-in Rock, IL from September 28-29. I found two other activities in the region that I could take in for an extended 3-segment trip. My trip started on September 27 and ended on October 2. I flew into Nashville, TN from Washington (DC) Dulles Airport that is about 20 miles from my home.

Trip Segment 1: Keokuk, Iowa and Hamilton, Illinois

Two years ago my wife and I went to Geodefest in Hamilton, IL. Even though the fest is in Illinois and the geode collecting trips are in Illinois and Missouri, the geodes are all named for the earliest collected geodes in that region from Keokuk, Iowa. Today most Keokuk geodes are not collected in Iowa. In 2016, as neophytes, we collected quite a few geodes. However, not having what I call the “gift of the heft,” a lot of our geodes were solid and “undesirable.” Probably better than the collecting was the silver picking from the many dealers there. My take from these dealers included some treasures for my other collecting interests, including agates and fossils. As for fluorescent minerals, there were many more options than you might expect for a Midwestern show. I saw quite a few well-known fluorescent minerals, such as Dugway geodes and Mexican adamite, for sale the first day but I did not purchase any of these, as I focused on fluorescent Keokuk geodes. There must have been some other fluorescent collectors there, because by the end of the fest, these better known fluorescents were sold. The major new finds for me were a few moderately MW FL Midwestern calcites. The calcites included those in Keokuk geodes from Iowa, Missouri and Illinois. Some of the geodes have cream or golden colored fluorescent rinds, too. There were also beautiful natural light calcites from the Linwood Mine in Iowa and the Sweetwater Mine in Missouri. Most of these calcites are quite beautiful MW fluorescents in shades of rose-pink and magenta, also, but they are only moderately bright. Of course there were very reasonably priced beautiful natural light Keokuk geodes, too.

But that was in 2016 and this is 2018. I had such a good silver pick collecting time at the fest in 2016 that I decided to make the long drive to Geodefest on Thursday and then the next day drive back to the Midwest FMS meeting, which included a collecting trip at the Annabel Lee Mine about 6 hours away on Friday night starting at 6 pm. To make it there in time for the collecting trip I had to make it a quick silver pick collecting trip at the Geodefest dealers. I was not disappointed. Even though the fest officially started at 8 am on Friday, several dealers opened up Thursday night for a sneak preview. The first rock I bought was a miniature yellow and violet crystalline fluorite from Cave-in-Rock, IL (see photos 2a and 2b below). The dealer had other nice and larger fluorite crystals but none glowed like that one. I also found some Kentucky agates and one turned out to be fluorescent (see photo 5). There were no fossils that I “had to have.”

Friday morning I picked up a few more (I already have around 10) MW fluorescent Keokuk geodes (see one at photo 3) and some natural light geodes. The few Linwood Mine calcites there did not entice me and there were no Missouri calcites that I saw. However, the most interesting finds of the show for me were some calcites and fluorites from the Waterloo South Quarry in Black Hawk County, Iowa (photo 1 below). These were similar to the famous fluorites and calcites from nearby and closed Pints Quarry in Raymond, Iowa. These fluorites are organic-activated and glow and afterglow creamy-colored in all waves. The calcites are a comparatively weak pink. One of the dealers who had these Waterloo South rocks also had some apparently self-collected LW two-color massive fluorites from Luna Co., NM (see photo 4)and weak lilac SW strong afterglow and LW blue FL (no afterglow) botryoidal fluorite, also from Luna Co., NM. So I was happy with FL Keokuk geodes from two new locations and some nice FL fluorites (plus I enjoyed seeing old friends).

Figure 1 (left): Fluorite and calcite crystals, Waterloo South Quarry, Iowa. Figure 2a (center): Fluorite (visible light), Cave-In-Rock, Illinois. Figure 2b (right): Same fluorite specimen shown in Figure 2a, showing fluorescent response under short wave UV.

Figure 3 (left): Calcite geode, Eastern Adams Co., Illinois; seen under mid wave UV. Figure 4 (center): Fluorite and other unknown minerals, Luna Co., New Mexico, fluorescent response under long wave UV. Figure 5 (right): Kentucky agate, Estill Co., Kentucky; photographed under long wave UV.

Trip Segment 2: The FMS Midwest Chapter Annual Meeting

Chapter President, Chris Clemens, did an outstanding job arranging the Midwest Regional FMS Meeting and has a giant shout out from me. The first event was a collecting trip to the abandoned Annabel Lee Mine, north of Cave-in-Rock, on Friday night (see Figure 6). There were probably fifteen to twenty collectors there and most collected more rocks than I did that night. What I did collect was a bunch of chigger (or redbug) bites around my ankles. This in spite of my good friend Steve Caldwell’s warning that I did not heed. Steve sprayed down with DEET so I hope he fared better. In the daylight I had accumulated a large pile of candidate rocks that I had collected and cracked to check for fluorescence when it got dark. My one little keeper piece was a small two-color fluorite rock (see Figure 7). None of the other pieces were better than those I previously had collected from the area.

Figure 6 (left): The Annabel Lee Mine headframe at sunset. Figure 7 (right): Fluorite specimen (approx. 2 inches across) collected from the Annabel Lee Mine, showing fluorescence under long wave UV.

I returned to my motel room in Harrisburg, IL where I lamped my finds and ended up sleeping poorly as my little nemeses had their way with my ankles. It was my own fault. I should have purchased some cortisone ointment, as I did the next day. That helped almost instantly but I was plagued for the next several days with these irritating guys. Moral of this story: don’t be like me, be like Steve, spray (your legs, knees and waist) before you leave.

The FMS Midwest Regional Chapter meeting was on Saturday morning at the Ben E. Clement Mineral Museum in Marion, Kentucky, not far across the Ohio River from the Annabel Lee Mine. There were about 35 attendees. The meeting started with donuts and coffee and show/tell, swap, and sale of glowing rocks. The Museum Staff were very gracious and wonderful site hosts/hostesses. The museum shop had lots of natural light and FL rocks for sale including some accessed from the Ben E. Clement collection. Ben Clement’s son Ed gave us a tour and spoke about his father’s collecting/collections and the museum history. My favorite part of the tour was the lights out segment in two particular rooms containing fluorite crystal and cleaved crystal specimens, here we could fire up our convoys and look at Ben Clement’s magnificent fluorites under UV. I have regrets that I did not attempt to take some cell phone photos, but it was understandably crowded with admirers. Photo 9 is the museum fluorescent mineral display. We returned to the meeting room for a pizza lunch. There was a brief business meeting and a group photo (see Figure 8). We then prepared for the three other field activities for the afternoon.

Figure 8: Group photo of attendees of the 2018 Annual Meeting of the FMS Midwest Chapter. This year's meeting took place on the weekend of Friday, September 28th and Saturday the 29th. Held at the Ben E. Clement Mineral Museum in Marion, Kentucky, this well-attended event attracted about 35 members from as far away as Wilmington, North Carolina and Ashland, Wisconsin.

Figure 9: The fluorescent mineral display at the Ben E. Clement Mineral Museum.

After crossing the Ohio River by ferry from Kentucky into Illinois, the first half of our caravan paused in Cave-in-Rock because we had more than one ferry-load of cars in our group. From an earlier trip I remembered the “famous” Cave-in-Rock building with fluorite and other rocks in its front wall face (see Figures 10a and 10b). When the next ferry arrived with the rest of our group, we left scenic Cave-in-Rock.

Figure 10a (left): Building in Cave-In-Rock with storefront constructed from fluorite. Figure 10b (right): Close-up of building face showing the fluorite construction material.

The next activity was scheduled to be collecting at the Parkinson Prospect off Illinois route 146 east of the town of Golconda, IL. After the Parkinson Mine we were scheduled to visit to Gary Griffith’s house to mine fluorite with the silver pick. However, when we contacted Gary he found that Gary needed to leave by 5 pm. So we went to Gary’s house first.

Gary Griffith is the last miner of fluorite in the fluorspar belt of Illinois and Kentucky. However, he mines only for mineral specimens. Our caravan of more than 15 cars crept down the country road in front of his house and parked. There were areas with large fluorite specimens on metal grates and calcite specimens in a pile on the ground. Gary also had egg cartons filled with octahedra that he had cleaved from fluorite that was not suitable for collector specimens. When we were there he did not have many museum grade specimens for sale, but that was the other type of fluorite he had for sale. Many of us armed with convoys looked at all of these types of material and traded money for rocks. My cart ended up with 8 fluorites/calcites and 8 cleaved octahedra for my sons and grandchildren (see Mark Cole’s photos, Figures 11a and 11b, of one of the rocks I bought from Gary). After all purchases were completed, Gary quickly and expertly demonstrated the preparation of a fluorite octahedron from rough fluorite (see Figure 10). He also showed us the material sold as fluorspar for commercial purposes. I did not get a close look but it appeared to me to look like brown granular hard masses of rock.

Figure 11a (left): Chapter members search the piles of fluorite and calcite specimens at Gary Griffith's house. Figure 11b (right): Gary Griffith does a demonstration of how to cleave a fluorite octahedron.

From Gary's house, we quickly left for the Parkinson Mine, which was well-covered with vegetation. The spoil piles were ample and evident. I brought four white FL calcite rocks out of the prospect but none of these made it back home. An interesting collectable from the prospect was drill cores, some of which were fluorescent after the encrusting mud and dirt has been removed. Thanks to David and Janyce Sorrells for leading us on this trip.

Figure 12: David and Janyce Sorrells collecting at the Parkinson Prospect.

The caravan then split up with some cars going to the Annabel Lee Mine and others going to the Minerva #1 Mine both north of Cave-in-Rock. I am not sure what happened at the Annabel Lee Mine, but I heard collecting was good. There were about ten cars at the Minerva Mine, when we arrived just about at dusk. My favorite approach to collecting there was not possible at this hour: collect large rocks from the stream bed and edge of the filled-in remediation area and crack them open, and leave them in a pile until it is dark enough to lamp them. Plan B was to surface gather as many candidate rocks in the remaining light and pile them up for lamping in the dark. This did not produce much interesting material for me, only a couple of massive orange FL calcites. After darkness set in, I decided to scan the gravel for small rocks for my grandchildren. After observing most folks hunting with convoys, understandably at this fluorite location, I decided to scan the area with my SW to look for red-fluorescing calcite. I had limited success, but I did find a few small ones (see photos 12 and 13). Tired and with itching ankles, I left my colleagues for my lodging.

It was a fun meeting/trip and exciting to collect with so many glowhounds. It will be difficult for Chris to top this next year. The Midwest is not fraught with locations where the general public can collect beautiful fluorescent rocks. Maybe next year the group will collect Yooperlites.

Figure 13: Fluorite specimen collected from the Minerva No. 1 mine seen under visible light (left) and long wave UV (right).

Figure 14 (left): Calcite and fluorite collected from the Minerva No. 1 mine, showing fluorescence under long wave UV. Figure 15 (right): Calcite and other unknown minerals seen under long wave UV.

Trip Segment 3: The Visit to Cole Mountain

I flew to Nashville rather than St. Louis because I wanted to visit Mark Cole, in Dowelltown, TN. Mark is my fluorescent rock mentor and probably the most skilled fluorescent rock photographer in the world. I asked ahead of time if we could collect at the Woodbury (Cannon County), TN geode location about 20 miles south of Dowelltown. On the internet and at Mark’s house I had seen the geodes with organic inclusions from this site and hoped to be able to collect one of my own.

My usual rock collecting activities at Cole Mountain include collecting with the silver pick in the rock room and the wall. Not long after I arrived I noticed a weather forecast of rain on Monday, therefore I asked Mark if he could reschedule the field trip to the Woodbury roadcut to Sunday. After picking up supplies in the beautiful little town of Smithville, we headed to Woodbury.

The collecting heyday for the Woodbury roadcut occurred when the U.S. 70S was being widened a few years ago. Word spread quickly and the site was heavily collected then and since then. This meant we probably would only be able to collect only a limited number of geodes. The spoils from the original road-widening event are nearby but are mostly covered with vegetation. Some of these of spoils are in the open on top of the edge of top of the roadcut, but we did not try to collect any of these. The color of this older host rock is a light gray. The Warsaw Formation in the roadcut is not much more that about 10 feet high. Geodes are found throughout the roadcut but are more numerous in the middle layers. Geodes appear to be mostly white in a dark gray fairly dense and hard bituminous dolostone (see Figures 15a and 15b).

Figure 15a (left): Woodbury, Tennessee US 70 South roadcut. Figure 15b (right): Close-up view of the Woodbury roadcut showing geodes in situ.

The many folks who collect there remove any loose or almost loose geodes in the roadcut wall. Most of the geodes are hollow and almost all are removed from the matrix/base rock with great difficulty. We collected what we could from geodes that were in loose pieces of matrix on the ground. Only a few of these were free of matrix. The outside shell of the geodes is quartz. However, some contain calcite, dolomite and a host of other minerals. The freshly removed dark gray bituminous dolostone host rock from the roadcut wall smells quite strongly of organics like asphalt. It is this organic content that gives the geodes their fluorescent boost. Some of the calcite (red-orange) and dolomite (blue-white) is fluorescent from activators that are not organic, but the fluorescence in quartz, and most of the calcite, is the result of the organic chemicals in the host rock or matrix (see Figure 16). Colors in SW and LW range from orange, yellow-orange, yellow, blue-white, and white.

Figure 16: Woodbury geode showing fluorescent response under short wave UV. The geode is composed primarily of quartz, calcite and dolomite, and measures approximately 5 inches across.

The prettiest geode we found on this trip was yellow fluorescing quartz about the size of a half of a small grapefruit (see Figures 17a and 17b). Unfortunately, this geode was in a large, heavy chunk of host rock about one foot square and about 4 inches thick. After much directed pounding on the rock with two medium weight hammers, I proposed that we try a large sledgehammer. Mark already had all of these geodes that he wanted so he let me do what I wanted with it. After about one smack with the sledgehammer a significant part of the geode popped off in several pieces leaving a smaller matrix chunk and a smaller geode. So as not to completely ruin the geode with further hammering, Mark wisely recommended using a diamond saw cutting the geode off the matrix. Mark expertly cut off the geode into a nice table decoration. One of the attractive features of this particular piece was a child’s little finger-sized quartz pillar projecting from the middle of the geode. This little feature survived the pounding and the sawing. It is a lovely keepsake from a wonderful memory.

Figure 17a (left): Woodbury geode with quartz, seen under visible light. Size is approximately 4 inches across. Figure 17b (right): Same geode showing fluorescent response under short wave UV.

When the vegetation cover dies off from the spoil piles, I would like to spend a couple of hours at dusk or early evening at the roadcut area. I would select geodes by fluorescence. On the next day I would try to downsize the matrix on these selected rocks off-site for smaller pieces of host rock and on-site for the larger pieces. I don’t think it would be permissible to stay overnight at the site.

It was another delightful and successful visit to Cole Mountain. I hope to visit again.

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