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  1. It looks like it could be Jasper? Interestingly, it has well formed crystalline structures which are very bright silver, are magnetic, and don't seem to oxidize. They are single crystal structures dispersed throughout the stone. As a reference, the whole stone is about 1.5" long. I actually found it metal detecting in a wood chip playground and it range up positive. I know it isn't valuable, just a curiosity. Thx, Brian
  2. Here are a few references to articles, etc on the California & Nevada Palo-river valleys found on older forum posts you may find of interest. “The Tertiary Gravels of the Sierra Nevada of California”, Lindgren, W. 1911 (book) “The upper reaches of the Sierra Nevada auriferous gold channels, California and Nevada”, Garside, L. J. 2005, Nevada Bureau of Mines and Geology. (downloaded from older forum link?) “Origin of gold in placer deposits of the Sierra Nevada foothills, California”, Christensen H. W. , Nevada Bureau of Mines and Geology, 2015 (downloaded from sierrageology.org). The attached photo is looking south over “Benson Lake” located in the backcountry of Yosemite National Park. The ridge line on the left (west) in the photo extends south from Piute Peak as referenced by Lindgren beginning on page# 214 of the 1911 “Tertiary Gravels”. The Lindgren photograph found between pages #218 and #219 is of the Tertiary (Eocene) Tuolumne River channel crossing east to west down ridge (south) of the lake, above and west of Piute Canyon. If you were to go to “Google Earth” you can fly around this actual channel crossing in 3D. Located down stream, near Big Oak Flat, on the tertiary Tuolumne River is one of the two richest placer deposits discovered in California. The first of the richest placer deposits was deposited by a branch of the tertiary Calaveras river into Columbia basin (CA, Columbia State Park). Both of these placers deposits are located east of the main Motherlode belt but may have crossed portions of the east lode belt (if either lode deposit existed or had raised 55 million years ago.) As a side note: “Table Mountain” located in both Calaveras And Tuolumne counties is at least 30 million years younger than these Eocene channels. The Table Mountain channel picked up placers at the cutting of the tertiary Calaveras channel at Columbia then again at the lode crossing near Woods Creeks, Jamestown. Per the article on the “ upper reaches of SN gold channels”, 2005 the central channel of the tertiary Yuba River originated near Yerington, Nevada. Seems the majority of the 1848 California placers were taken before these ancient Eocene channels crossed the main California lode deposits. Although you are allowed to fish but not detect within a national park, I have heard you may still be able to detect in Nevada. Just keep in mind that unlike YNP park rangers, old miners are neither as well dressed nor nearly as polite. Enjoy the read.
  3. https://trib.com/news/local/casper/a-wyoming-crater-field-may-offer-insights-into-our-solar-systems-workings/article_0e0eae2c-4426-11ed-bcf6-e7dbc7b57469.html There are varying theories as to the origin - including that we once had a second moon! Or maybe smaller orbiting sub-moon type body which got shattered by an impact and rained onto Earth. The article doesn't cover this, but of note is that the formation in which this massive field of fossil craters is found in matches up with the largest extinction event in history - the Permian-Triassic extinction event - which is much larger than the one that killed the dinosaurs 200 million years later. In any event, this is an extremely interesting discovery. I believe this field probably extends beyond just Wyoming and may be a national scale, or maybe even potentially a global scale occurence with more research. The craters themselves are visible on aerials if you look closely, but are so old that any actual meteorite material has long since weathered away, but shock glass is still there.
  4. Hope you are all out digging on this holiday weekend!! Often times when detecting for gold nuggets in dry placer conditions I get clumps of clay or dirt containing gold. What sort of clumps or lumps does your pay layer produce? This lump came from a layer of decomposing bedrock hard pack layer above a stream bed high on a flat no longer part of the current creeks flow.
  5. Greenland could be a hot spot for coal, copper, gold, rare-earth elements and zinc, according to the Geological Survey of Denmark and Greenland. https://www.cnn.com/2022/08/08/world/greenland-melting-mineral-mining-climate/index.html?utm_source=pocket-newtab Easier than mining an asteroid -- maybe good practice for that.... (Article from 8 Aug, so a week ago as I post. I don't think I'm duplicating a previous post/thread.)
  6. My son asked me what book to get that explains the geology and geological indicators to find gold sources? So, I said that I would get some suggestions from the seasoned gold hunters on Detector Prospector, instead of searching the internet where you will find that one person states that his book is the best, ... and, etc., etc. (My experience is somewhat limited, far from pro.)
  7. I don't know exactly where to put this so I'll start here. Maybe Clay has it on his links or someone else has posted it but it got me to some maps I would not have found. I still don't understand most of the nomenclature. https://ngmdb.usgs.gov/mapview/?center=-97,39.6&zoom=4 MapView Betaby the NGMDB MapView lets you explore some of our favorite geologic maps from the NGMDB (USGS/AASG).
  8. I’m curious to how you all see the mineralization of the soils you detect compared to other locations. Our soil here in central Arizona seems to be fairly mineralized. But, we haven’t been detecting anywhere out of state to let us effectively compare. Here’s a USGS map showing relative iron concentration in US soils. There appears to be heavy iron concentrations in the Pacific Northwest. Does this reflect your experience on the ground? If so, has this affected what you choose to swing? If not, how do you think your soil compares to elsewhere? us iron concentrations.pdf
  9. Flooding like nobody has seen in over 100 years is taking place in some of the historic gold districts of Montana, Idaho and beyond. An impressive late season snow pack followed by warm temps and rain has the rivers and gully''s a boom'n. Material that hasn't moved in over a century is on its way. Time to get your detector, sluice box, highbanker, dredge suits, etc. ready. Could be once in a lifetime prospecting opportunity, still keeping in mind the property damage is extreme & tragic for many and our hearts go out to them.
  10. I would say my panning skills have improved quite well over the past couple of months since I began “looking” and I no longer have to use my magnifier to check wether it’s gold in the pan or not. The burn I pan is quite peculiar,as in the deeper I dig the less gold I find.I might find a couple of small flakes only a foot deep,but then dig down another two and only find tiny specks. I got talking to a guy yesterday called Gary,who pans the same area and he says the same thing,and we both agreed it must be something to do with the clay layer and that we believe the gold isn’t sinking beyond this layer.I would say the clay layer is false bed rock.Gary mentioned that he found a 2.4g nugget sitting on the clay layer but that he didn’t find anything else around it. Gary is the first person I have spoken too while panning and although he has only been panning himself for 5yrs,it was good to know that I’m not the only one who has noticed the lack of deeper gold. The clay layer has a very smooth consistency and is grey in colour.Some areas of clay do hold gravel but in general if I mash a chunk up it turns to nothing but a cloud. There is also not much in the way of black sand in this little stream,mostly blonde sand.There are flecks of platinum,zinc,sulphur,copper and iron to be found in the pan and some lead here and there. There was a gold mine near the top of one of the feeder streams and I will be going for a venture to see if I can find it.
  11. I just read with interest an event that changed the landscape of Eastern Washington State. There is some mention of Montana so these events may have changed where gold has been moved and where it is left. https://www.smithsonianmag.com/science-nature/devastating-ice-age-floods-that-occurred-in-the-pacific-northwest-fascinate-scientists-180979749/?utm_source=smithsoniandaily-dek&utm_medium=email&utm_campaign=20220419-daily-dek&spMailingID=46715100&spUserID=MTMxNjg2MzE5MzQ5NgS2&spJobID=2222101253&spReportId=MjIyMjEwMTI1MwS2 A little bit more research provided a more detailed link. https://hugefloods.com/Scablands.html
  12. I have been working a creek and have done fairly well. There have been at least 3 spots where there seem so be a strong signal in the bedrock , which is mostly shale. I keep a rock hammer and chisel in my bag and have tried to dig some out. I feel like it's just a particularly hot spot of ground, but I dont know that it is, they seem vary localized. Any thoughts?
  13. Nick Zentner, Geologist CWU discussion on the Liberty WA placer & hardrock gold deposits.
  14. Nick Zentner, CWU visit inside Rob Repin’s mine in Liberty, Washington.
  15. Here a video link to the richest pocket gold mine in the gold country if not the state. Take note of the depressions from the wooden cross ties of ore cart tracks. A lot of barren quartz broke a lot of want to be mine owners but when they mined into a crossing the gold was in sheets. The contact was along the north south trending limestone formation. Later the drifts were used for passage ways between the cathouses and underground speak easies. Back in the 1950’s one of the sons of the then mine owner ran an ore cart off the tracks into a support timber. He discovered enough high graded gold buried under the foot of the timber to buy himself a new pick up truck and then some. Years later I would have the privilege of remodeling one of the above ground madam’s room, which was connected to this mine, into a bank manager’s office. The original cathouse door with glass window advertising, which led many a miner, logger & cowboy in the wrong direction, is still around back. I still own stock in that bank. Enjoy, few are alive that have ever got view inside of this historic mine.
  16. Stumbled onto this interesting article form another site...... Not sure where to post this but Steve can relocate it where he see's fit? https://www.westcoastplacer.com/paleochannel-hunting-guide/
  17. You have had a lot of success over the years. I imagine you have found some wonderfully large masses of gold. Think about each of those for a few moments, especially those in the lower 48. Does anything appear as a common feature of their locations? Surely not everything would fit the same mold, but was there anything present frequent enough to indicate one location might be a little bit more likely to yield big gold than another? Thanks
  18. The Mystery Formation of Extremely Rich Gold Veins Might Finally Be Solved MICHELLE STARR 24 MAY 2021 Gold, for all its wonderful uses, isn't hugely abundant in Earth's upper layers. For each ton of crust material, there's an estimated just 0.004 grams of the precious metal. Yet somehow, there are regions that contain "bonanza" abundances - hyper-enrichment, in the scientific parlance. How these gold veins form in time spans as short as days from hydrothermal systems that only contain trace amounts of the metal has been a geological mystery. It's one that now has an answer, from the most unlikely of clues: the separation and clumping of fat particles in soured milk. "Scientists have long known that gold deposits form when hot water flows through rocks, dissolving minute amounts of gold and concentrating it in cracks in the Earth's crust at levels invisible to the naked eye," geoscientists Anthony Williams-Jones and Duncan McLeish of McGill University in Canada stated in a Q&A. "In rare cases, the cracks are transformed into veins of solid gold centimetres thick. But how do fluids with such low concentrations of gold produce rare ultrahigh-grade gold deposits? Our findings solve the paradox of 'ultrahigh-grade' or 'bonanza' gold formation, which has frustrated scientists for over a century." Milk is an aqueous solution made up of several components, one of which is microscopic globules of fat. At the pH level of fresh milk - very close to neutral - these fat particles have a negative charge, which causes them to repel each other. The souring process involves bacteria in the milk converting lactose to lactic acid, lowering the pH level accordingly. This causes the surface charge on the fat particles to break down, and the fat particles separate from the milk serum and clump together with each other via coagulation, forming a sort-of gross decomposing milk fat jelly. Williams-Jones, McLeish and their colleagues found a similar process when using transmission electron microscopy to study gold deposits from the Brucejack Mine in British Columbia. This is one of the spots around the world where bonanza-grade mineralization can be found, up to 41,582 grams per ton. It's long been accepted that gold is transported by way of fluid through Earth's crust. However, in order to reach the abundances found in hyper-enrichment zones, previous studies suggested that the gold may have been dissolved in high concentrations in fluids containing chlorides or bisulfides, and transported and deposited that way. The other possibility is a colloidal solution, with solid nanoparticles of gold dispersed throughout hydrothermal and geothermal fluids. Since the gold nanoparticles hold a charge (like milk fat), they repel each other. When the charge breaks down, the gold particles clump together in a process similar to coagulation, known as flocculation. This has been indirectly demonstrated in the past; now, McLeish and colleagues have observed how it actually happens. "We produced the first evidence for gold colloid formation and flocculation in nature and the first images of small veins of gold colloid particles and their flocculated aggregates at the nano-scale," Williams-Jones and McLeish said. "These images document the process by which the cracks are filled with gold and, scaled up through the integration of millions of these small veins, reveal how bonanza veins are formed." For this process, the concentration of gold in the geothermal fluids only has to be a few parts per billion. It flocculates to form a jelly-like substance, which gets trapped in cracks in Earth's crust to form rich gold veins. This finding suggests that rich gold deposits may be more common than we thought, and may have occurred in several other contexts than previous estimates had allowed for. If other studies and further examination can back it up, the research could give us a new toolkit for understanding and locating gold deposits around the world. "We suspect that the colloidal processes that operated at Brucejack and other bonanza gold systems may also have operated to form more typical gold deposits. The challenge will be to find suitable material to test this hypothesis," Williams-Jones and McLeish said. "The next step will be to better understand the reasons why colloid formation and flocculation occurred on the scale observed and reconstruct the geological environment of these processes." The research has been published in PNAS.
  19. I'm interested in any information on how gold veins/ lode deposits become offset and how to attempt to predict the amount of offset. Anyone have information on this? Thanks, RiverRat
  20. The earth has been warming and glaciers retreating for over 15,000 years. Almost everything in the part of Alaska I lived in was recently exposed by glaciers and been prospected the last couple hundred years. Glaciers are nature's bulldozers and they destroy and mix. The gold distribution in glacial material is generally random and sparse. Where water has had time to work glacial deposits new placers can form, but the short geologic time spans we are talking about usually mean small erratic deposits. The good news is that also means you can maybe find a gold nugget just about anywhere in glacial material. If you watch the video a second time and pay attention to the area that becomes Alaska you will see that Anchorage, on the southern coast, was buried under 3000 feet of ice not too long ago. The interesting part is northern Alaska is largely ice free. This is extremely important. The placers are much older and more extensive in Interior Alaska than in the southern coastal areas. The northern US was heavily glaciated and much of the material was pushed down from out of the north in Canada. I find glacial terrain interesting because glaciers have melt water running under them and along the edges, which form small oddball placers in the strangest places, and other placers are possible in the large outwash areas. I am discovering there was a lot more glacial activity in the Sierras than I would have imagined and so this is still very relevant for me prospecting in California. These links may not be for your exact area but all contain good information about glacial geology and prospecting. Great freebie article Gold in Kansas And a small related article at the ICMJ Undiscovered Placer Deposits in Alaska Really good stuff starting page 117 on Gold Placers of Colorado Placer Deposits of the Yukon Geology of Tertiary and Quaternary Gold-Bearing Placers in the Cariboo Region, BC Here is some really technical stuff for those so inclined Glacial Geology & Prospecting Glaciers of California A much more prospector friendly version can be had in an excellent but pricey book by Chuck Lassiter, Midwest Gold Prospecting at http://www.midwestprospector.com/book.html I have a copy in my library of the best of the best. It is a high quality book with color maps and illustrations and a no-brainer at about half the cost. For $29.95 you have to just love books as much as me as that is as much as the Chris Ralph encyclopedia and this book would be a chapter in Chris book. That said, I have never seen the particular subject of glacial region prospecting covered better and more understandably anywhere else. It would be the go to primer for anyone interested in the subject.
  21. Interesting! Will be useful when we eventually have a colony there.
  22. So what caused it to break away? Here is more on that theory. https://www.sciencemag.org/news/2021/03/remains-impact-created-moon-may-lie-deep-within-earth
  23. Hello, I was out this past weekend with my Gold Monster 1000. Here is a picture of a rock that I came across that had crystals and what I believe is black sand. I have come across black sand by it self and has done the same issue with my machine. Reading and sounding hot and then a blank sound as well. 1) I assume that you can find black sand like this still in a rock with Quartz. 2) Is is not true that usally when you find black sand you may end off finding gold as well because black sand and gold go together. here are four pictures of the rock. Allen
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