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Most people are familiar with the Conasauga Formation when they think of Georgia's Cambrian record, but the Peach State has a paleontological history dating back several million years before the Conasauga was deposited. Indeed, the oldest fossils in Georgia date back to the early Cambrian, and consist of a diverse form of worms, brachiopods, trilobites, and other creatures such as hyoliths and archaeocyathids. This early Cambrian record is largely divided into three formations, from oldest to youngest the Weisner Formation (part of the Chilhowee Group), the Shady Dolomite, and the Rome Formation. All of these formations, as well as the overlying middle Cambrian rocks of the Conasauga Formation, are well exposed in the Rome and Cartersville areas. Cartersville is a mid-sized town in North Georgia with a rich interconnection between history and geology. Situated near the confluence of three major geological provinces (the Valley and Ridge, the Blue Ridge, and the Piedmont), the Cartersville area was uniquely positioned for the discovery and future development of a variety of mineral resources. Wide scale mining began in the mid-19th century with the establishment of the Etowah Iron Works along the Etowah River. Although the bulk of the works were destroyed by Union forces during the Civil War, mining not only continued in and around Cartersville but actually expanded in the post-war period. Iron was the principal product for a while owing to the region's rich limonite deposits, but by the turn of the century ochre and barite production also became prominent, if not more so. Mining operations peaked by the middle of the 20th century, but some active mines remain in the area, and they continue to be a favorite with mineral and fossil collectors. Thankfully, this past history of mining, combined with the recent construction due to Atlanta's explosive growth, has exposed rocks typically left buried under the thick clay and vegetation of North Georgia. The Shady Dolomite was, and still is, the focus of the brunt of the ochre mining around Cartersville. A carbonate unit, the Shady is easily weathered in North Georgia's humid and rainy climate, dissolving much of the rock and underlaying the ground in a thick, reddish clay. Due to the nature of the weathering, however, distinct beds can sometimes be seen in cuts made into the Shady, as shown in the above photo from a construction site in Cartersville. Another exposure of the red clay residuum made out of weathered material from the Shady Dolomite. Although the carbonates of the Shady are frequently weathered into a thick, red muck, this weathering process typically uncovers a wide variety of rock types that are more resistant to chemical attack, and which would have otherwise been locked into the dolomite. At exposures like the one above, pieces of shale, iron oxides, and chert are common. Alongside the chert are fossils from some of the oldest reef communities in Georgia. This small piece of rock contains fragments of archaeocyathids, ancient sponge-like organisms that once established reefs in the early Cambrian sea. Alongside archaeocyathids, other fossils like trilobites and brachiopods are sometimes found in the Shady, but I didn't find any personally. Aside from iron and ochre, Cartersville was an important center for barite mining around the turn of the century. Most barite mines were located east of town, near the contact between the Valley and Ridge and the Blue Ridge provinces. Although most have been filled in or flooded, one pit that is still left can be seen at Pine Mountain east of town. A few pieces of barite ore line the trail leading up the mountain. A small piece of barite ore from near Cartersville. The walls of a former mining operation near the base of Pine Mountain contrasted with an image of a similar mine when in operation. Leading up the trail at Pine Mountain, one travels across geologic provinces. The valley floor is underlain by rocks of the Shady Dolomite and Rome Formation, part of the Valley and Ridge province, while Pine Mountain itself lies within the Blue Ridge. Climbing up Pine Mountain, you begin to sense that change reflected in the rocks underneath you. The red clay and chert residuum of the Valley and Ridge gives way to brown and white dirt, and the chert and dolomite boulders give way for quartzose sandstones, quartzites, and schists. Along the trail, numerous pieces of quartz sandstone from the Weisner Formation are exposed, and in these boulders you can sometimes catch glimpses of the earliest recorded life in Georgia! The picture here shows a sandstone boulder with a couple of well-worn Skolithos linearis worm burrows. Whereas the Shady Dolomite was deposited in a shallow, tropical sea, the upper Chilhowee Group was deposited in a near-shore environment as indicated by the coarse sediment. That means that 530-550 million years ago, during the early Cambrian, what is now a mountain would have been a warm, sandy beach! And, although they may not seem like much, the humble tubes in the rock illustrate a time when life was not everywhere abundant, and the diverse lifeforms we find at beaches today had yet to appear. Climbing the rocky trail to the summit, one is well-rewarded with a view of the entire Cartersville area, including a view across much of the Piedmont to Kennesaw Mountain beyond, and across much of the Great Valley to the Armuchee Ridges. One can also get a sense of the legacy of intense mining that took place around Cartersville from the many red-colored pits scoured into the nearby hillsides, ghosts of operations past and present. On top of all of that, one can also visualize the impact geology has on the topography of an area. Being the intersection of so many geologic provinces, the Cartersville area is marked by numerous faults, folds, and other complex structural geology that has left pockets of one formation nearly surrounded by pockets of another. This has contributed to the hilly nature around Cartersville, as the comparatively resistant rocks of the Rome Formation and Chilhowee Group forms island-hills in the sea-valleys of the Shady Dolomite. The view from Pine Mountain. The red areas are current and past mines around Emerson, Georgia, just south of Cartersville (which includes the buildings in white). The hills here, which make up part of the Allatoona Mountains, are held up by resistant units like the Chilhowee and Rome while the valleys are underlain by softer carbonates like the Shady. On a clearer day you could make out the Armuchee Ridges lying at the western edge of the Great Valley, a synclinorium of Cambro-Ordovician rocks that stretches from here all of the way to Quebec. I hope you enjoyed the report!

Hello. I found this in the area of Nornern California's Table Mountain. It's a volcanic plateau basalt messa. The Miocene lava flow that created Table Mountain is named the Love Joy Formation. It was heavily hydro mined for gold and diamonds in the late 1800s. This rock has basalt fragments embedded. Some shiny pulled areas like it's been melted. It's very light .75lb or .34kg feels consistent to pumice. I'm wondering if this is a product of the extinct volcano or some byproduct of the mining the volcanic ash? Thank you for looking!

These were found yesterday in Inglis, Florida at a mining facility. Our child would like to take them to school for show & tell. We are hoping to find out more information on them so that she can share with the class.

I found this near an old mining area in Idaho. Haven't been able to track down any specific info

I was recently in Park City, Utah, when I collected a few rocks from the dump of the old Thaynes Mine. I thought it was Quartzite at first, but then I did some research on the stratigraphy of the Park City District and began to doubt my assessment. From highest to lowest, the formations of the district are the Ankareh Shale, the Thaynes Limestone, the Woodside Shale, the Park City Limestone, and the Weber Quartzite. I am not certain of this, but I do not think the Thaynes Mine ever entered the Weber Quartzite. However, I did discover that the Park City Limestone contains some Quartzite inclusions, but I'm not sure if the mine even went that deep. Overall, I think that it is either Sandstone of Quartzite, but I'm not sure which, nor am I sure of the parent formation. Any input on this matter would be greatly appreciated. The specimen is a light bluish-grey, hard, fine grained, and has small pockets of carbonate residue in it.

Below are some talks on gem-bearing pegmatites Spectacular Gem Crystals: Pegmatite Pocket Formation and Survival Tom Campbell, Staff Mineralogist, The Arkenstone, Oct. 4, 2019 https://www.youtube.com/watch?v=SS50-WzOjvg https://www.youtube.com/channel/UCIqF4IlVr75GZMROmG3myEA Granitic pegmatites Formation and mining by Mark Jacobson, Retired Chevron Corporation, June 6, 2016 https://www.youtube.com/watch?v=1hDp9Bizq78 https://www.youtube.com/channel/UCIqF4IlVr75GZMROmG3myEA Pegmatites: An Update on Recent Production Peter Lyckberg, 2018 GIA International Gemological Symposium https://www.youtube.com/watch?v=jDpIKxWoq2M Yours, Paul H.

Reduction in protected land puts fossils (and science) at risk. https://cosmosmagazine.com/palaeontology/the-breaking-of-america-s-fossil-monument

I decided that today me and the boys would do something a little different. Instead of hunting for fossils, we were going after those beautiful, double terminated Herkimer Diamonds. It has been a little over 2 years since we have gone to the mines. I had promised them back in early spring, that I would take them there. But due to all the rain we were having, I had to put it on hold. Summer is not the optimal time to go for many different reasons. The heat, crowds, and lack of fresh material being the main reasons. But we got up early to try to be the first ones in line to buy our tickets, and succeeded. The mine opens at nine, we got there by 8:20. About 10 minutes later cars started pulling in. The first group was from Pennsylvania. It was their first time, so I passed on as much knowledge as I could to help make their hunt successful. I was a bit perturbed to find out that they no longer allow people to drive into the mine. So we had to lug all our tools a good distance before we could get started. There is to pits to this mine and we started at the first one. Due to the fact that I am much older than when I first started going, I don't try to break into solid rock like I used too. Unless I find an area that does not appear too difficult and looks very promising. Unfortunately there was debris everywhere which made digging into the floor practically impossible. So I decided to look for boulders to smash. When choosing this method you want to look for rock that is porous. The crystals form in vugs. So if a rock has holes in it, you have a better chance of finding crystals then trying to break rock without holes. After looking around I found a boulder that looked suitable. After breaking it down I found some small crystals in some drusy vugs. Even a couple decent calcite crystals. I collected the loose crystals, and left the tiny ones in matrix for others to find. I decided to go to the second pit, since that is where I have had most of my luck in the past. Mind you some time had passed and people were piling in. So we lugged all of our stuff even farther to get to pit #2. I hadn't paid much attention to the fact of how many people bypassed the first pit to the second. There were people in all the prime spots but they weren't even utilizing these prime spots the way they should. Most were newbies who didn't have the right tools. So I again started looking for boulders to smashafer whacking a couple to no avail, I spotted one that I got a good feeling about. I whacked it I few times and small pieces were coming off. Then after a few more whacks it split it half. When the one half fell over, my heart started racing as I saw a nice cluster of decent size crystals in a vug. I yelled for the boys to come take a look. That got some other peoples attention. Soon I had a group looking over my find. After they left, me and my oldest, David started looking on the ground and found some that had fallen off the cluster. Then I looked at the other half of the rock and thete was a single crystal in the other half of the vug. I asked David to help me carry the pieces of rock back to the car. Of course on the way we passed a lot of people who wanted to look at what we had. I didn't mind until one group basically grabbed the peices out of our hands and started passing it around before I could even say anything. It sidnt want to create a scene but I was close to going beserk. Finally I told them to give it bach before they damage anything. Then we gotback to the car where we put everything safe and sound.at this point we had been there for 3 hours in the sun and everyone was hot, tired, and hungry. I would have liked to stay longer as I would of liked for the boys to have found more of their one. But they were ready and I knew I was going to give them some of my finds anyways. When we got back home I tried trimming down the piece with the cluster and they all popped loose with minimal damage. That is what usually happens when trimming but now I have some nice loose crystals to admire!