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Found 61 results

  1. Collecting Native Silver & Related Minerals in Northeastern Ontario’s Silverfields Introduction… I’ve been cleaning and photographing some small native silver specimens that were found with a metal detector during my last few rockhounding visits to the silverfields of northeastern Ontario. They are commonplace examples of small silver that hobbyists can anticipate recovering from the tailing disposal areas of abandoned minesites, ranging in size from one-half to several troy ounces. The information and silver photos presented below may interest newcomers to the fascinating hobby of rock, gem and mineral collecting, particularly for those who have reasonable access to collecting sites for native silver and associated minerals such as the example displayed below. It is comprised primarily of rich, dendritic acanthite with some minor inclusions of native silver visible on the surface. Searching for Small Silver… When selecting an appropriate prospecting-capable metal detector for this application, consider the field conditions where you will be operating it. A large portion of your time will involve searching abandoned minesite tailing disposal areas because these sites offer you the best opportunity to find native silver and related minerals. (a) At many sites ferromagnetic susceptible substrates can be characterized as ranging from light to moderate, and will have little effect on a VLF detector’s ability to function effectively. But some areas, for example diabase dominant substrates, exhibit more elevated magnetic susceptibilities that to some extent will reduce a VLF metal detector’s detection depth and sensitivity, target ID accuracy, and discrimination reliability. The effects of harsh ground mineralization can be somewhat mitigated by operating a VLF metal detector in a true motion all-metal mode to maximize detection depth and sensitivity to targets. A smaller / DD coil will reduce the ground mineral footprint scanned by the detector, permitting the use of higher gain / sensitivity levels than would otherwise be possible. Regardless of target ID or the absence of it, ensure that all weak signals are investigated until the source is identified. An obvious alternative strategy to improve detection depth is to use a suitable PI detector for searching more difficult ferromagnetic ground mineral areas. A more recent Minelab PI model will ensure the best possible detection depth over such ground. (b) Consider the most frequent size of the silver you can expect to find with a metal detector. The small silver depicted in the accompanying photos is representative, and as noted above, range from about one-half to several troy ounces. They are typically larger coin-size targets detectable to very good depths, but keep in mind when choosing a suitable prospecting-capable VLF detector that most small silver is low conductive, and on average is characterized by a nickel target ID. (c) In some areas conductive pyrrhotite hotrocks are a real nuisance to both VLF and to PI detectors. Abundant pyrrhotite can render specific sites unsuitable for metal detecting. Target ID ranges from iron to low foil, with most pyrrhotite signals eliminated by upper iron range discrimination. My PI units, the Garrett Infinium and White’s TDI Pro, both generate enticing low conductive signals to solidly structured pyrrhotite, and similar to small, low conductive native silver, pyrrhotite PI signals must be dug. (d) Mining country, and abandoned mining camps in particular, are littered with iron trash of all sizes and description. Small, low conductive iron signals can be eliminated with suitable VLF iron range discrimination, but most non-descript small iron produces low conductive signals from my PI units. Similar to pyrrhotite, our PI units cannot reliably distinguish low conductive silver from low conductive ferrous trash. All low conductive PI signals therefore must be dug, and to do so is prudent fieldcraft regardless which PI brand or model is utilized for this detector-prospecting application. Incidentally, the same observation largely applies to VLF target ID reliability over deeper, weak target signals in more difficult ferromagnetic substrate conditions. Such signals tend to produce questionable readouts that either frequent or reside within the iron target ID range. To have any confidence in VLF target ID, it is necessary to remove surface material from deeper target signals until a reasonably strong VLF detection signal can be obtained. If any doubt about target ID remains, dig it to be absolutely certain of its identity. By comparison to low conductive iron, big compact iron such as larger drill bits and milling balls, and sizeable elongated iron such as broken pipes and implements, rail spikes, and drill rods tend to VLF target ID in the non-ferrous range. My PI units produce high conductive signals to large compact iron. A similar response, usually a double low-high or single low-high-low signal, is produced as the coil is swept lengthwise on elongated iron, whereas low conductive signals are normally produced when the coil is swept across the length of such targets. With native silver’s variable conductive potential (variations in size, shape, purity, structure) quite capable of producing both high and low conductive PI signals, the foregoing explains why all PI signals should be identified. While a large portion of our fieldwork in the northeastern Ontario silverfields is more suitably addressed with VLF units, we frequently use a ground-balancing PI unit for general scanning over tough ferromagnetic substrates where ferrous trash levels are tolerable. In these conditions we employ larger coils to improve detection depth over what VLF units can achieve. Additionally, our PI units eliminate or reduce most non-conductive iron-mineralized hotrock signals in the area. Such signals can be a particular nuisance when searching diabase dominant substrates with a VLF unit. Our VLF preference is to use mid-operating frequency range detectors for this application. Mid-frequency units respond reasonably well to both high and low conductive silver, and to weaker signals produced by low conductive particulate and sponge silver. By comparison to high frequency units such as my Goldbug2 for example, they are less vulnerable to elevated ferromagnetic mineralizations, and see both higher conductive targets and larger targets at better depths. Incidentally, low operating frequency units work reasonably well, but are less sensitive to low conductives. We operate both the mid-frequency White’s MXT and Fisher F75 for motion all-metal mode close-up scanning involved with removing surface material from hillslopes, trenching, sinking testholes, and for detecting excessively trashy areas requiring a discrimination mode, but there are other perfectly acceptable detectors that will perform well at these tasks. Your detector choice ideally should feature a target ID in a threshold-based motion all-metal mode, a discrimination mode, include a manually adjustable full range ground balance, a “fastgrab” ground balance for convenience and to assist with target signal evaluation, and a selection of searchcoil types and sizes. Which type of metal detector is best suited for this application? We operate the PI and VLF units described above to deal with variable field conditions and objectives, but the VLFs do much of the fieldwork here. Newcomers should begin with a VLF unit that incorporates the features outlined above as a minimum. You may wish to supplement your stock coil with larger and smaller coils to increase your versatility in the field. Once you have gained some field experience with the conditions as described above, and generally have learned more about collecting silver minerals, you can make a more informed decision as to whether acquiring a suitable prospecting-capable PI unit is a viable choice to satisfy your objectives in the field. Where to Look for Silver & Other Minerals… As a general principle regardless of the type of minerals one seeks, successful collecting invariably depends on knowing where to look and a willingness to do serious pick and shovel work. Surprisingly detailed information about where to search for many minerals is readily available online to hobby newcomers, with many collecting sites readily accessible by personal vehicle. On occasion, more remote sites or identified prospects will typically require a short hike. For example, extensive information about abandoned gold and silver mines can be accessed online, and many current government publications are available to interested hobbyists. My personal favorites include a series entitled Rocks and Minerals for the Collector authored by Ann P. Sabrina, in association with the Geological Survey of Canada. These publications supply practical, useful information pertaining to abandoned minesites throughout Canada. They provide road guides to accessible collecting locations, a brief history of a site’s mining operations, normally include production numbers for more prominent minerals such as cobalt, lead, zinc, nickel, copper, silver and gold, and usually provide a comprehensive list of mineral occurrences for each site. For casual or recreational prospecting enthusiasts visiting this area with limited time to search for silver ores and nuggets, select abandoned sites that will more likely produce detectable native silver based on past production numbers. You can detect these sites with the certain knowledge that highgrade silver was inadvertently discarded to the tailing disposal and nearby areas, sometimes in considerable quantity. The probability of successfully recovering specimen grade silver is sharply improved compared to searching for outback silver float, obscure prospects, or low production sites. To improve the likelihood of finding silver, try to identify areas where valuable silver was handled and transported. For example, look for evidence of surface veins, shafts, and storage areas where silver was graded, moved, and sometimes inadvertently misplaced. There are many plainly visible field indications of former mine buildings, mill sites, ore transport routes and abandoned trails. While quantities of silver were frequently discarded to tailing disposal areas, keep in mind that some highgrade silver was unknowingly included with waste rock for road and other construction projects. Hobbyists have also detected large specimen grade silver that was occasionally lost to spills on steep embankments, washouts, or sharp bends along the transport routes of the time. Incidentally, we occasionally see examples of careless or halfhearted retrieval techniques when only a few more inches of digging in tough ground would have unearthed quality silver that produced unmistakably solid, tight non-ferrous target signals that could not be mistaken for iron trash. A general suggestion to newcomers is to be thorough in all aspects of your fieldwork, examine abandoned digsites, and dig all questionable target signals until the target is identified. Briefly About Acanthite… As a related but slight diversion from the topic of searching for small native silver, depicted below is a small but massively structured example of acanthite / native silver recovered from the Kerr Lake area of northeastern Ontario. While selecting some reasonably photogenic small silver examples, I decided to include it here because valuable acanthite https://www.minfind.com/minsearch-10.html recoveries are a rather infrequent occurrence in my personal experience and therefore welcome additions to my collection. After some 30+ prospecting seasons, I’ve never detected acanthite as a stand-alone mineral. My acanthite finds have always contained some detectable native silver. For those unfamiliar with this mineral, acanthite is a dark silver sulfide (Ag2S) approximately comprised of 87% silver and 13% sulfur. Smithsonian Rocks & Minerals describe it as the most important ore of silver. Much of the world’s current silver demand is satisfied as a by-product from the refining of argentiferous (silver-bearing) galena. Galena, a lead sulfide, generally contains some small (< 1%) amount of silver in the form of microscopic acanthite inclusions as an impurity. Acanthite is occasionally misidentified as argentite by hobbyists, but the correct mineral classification when referring to silver sulfide (Ag2S) at room temperatures is acanthite. Both these silver minerals possess the same chemistry but different crystalline structures. Argentite forms in the cubic (aka isometric) system at temperatures above 177 degrees Centigrade (temperature slightly varies according to reference source). Below that temperature acanthite is the stable form of silver sulfide, and crystallizes in the monoclinic system (Smithsonian Rocks & Minerals 2012 American Edition, Eyewitness Rocks & Minerals 1992 American Edition, Wikipedia). The transformation of argentite to acanthite at lower temperatures often distorts the crystals to unrecognizable shapes, but some retain an overall cubic crystalline shape. Such crystals are called pseudomorphs (false shapes) because they are actually acanthite crystals in the shape of argentite crystals. Acanthite crystals frequently group together to form attractive dendritic (branching) structures embedded in light-hued carbonate rocks that range from rather intricate to massive. In the field, try to be visually alert to darker (typically sooty-black) acanthite that may be exposed while digging targets, trenching, or by chance encounters with recently exposed material. For example, the local township occasionally removes tons of tailings for road and other construction projects, resulting in fresh new surfaces for hobbyists to explore. Prominent Minerals Associated with Native Silver… Native silver, acanthite, pyrargyrite and proustite ruby silvers, stephanite, and other collectable silver minerals primarily occur in carbonate veins in association with gangue minerals such as quartz, chlorite, fluorite, barite, albite, hematite, magnetite and many other minerals related to relatively shallow epithermal deposits. Attractively structured native silver embedded in light-hued carbonates, or for example in association with other silver minerals such as acanthite and proustite, is highly valued by the mineral collecting community. For newcomers incidentally, structure refers to how the silver is formed, examples include massive or nuggety formations, plate, disseminate or particulate, sponge, highly crystalline, and various dendritic or branching patterns as illustrated by the native silver example in the multi-photo below. The native silver in this area is intimately associated with major cobalt-nickel arsenide deposits that include notables or collectibles such as safflorite, cobaltite, nickeline, and skutterudite. A number of these ores, typically arsenides and sulfides, produce perfectly good signals from VLF metal detectors. Solidly structured nickeline (aka niccolite), a nickel arsenide, is a fine example that can generate strong signals from both VLF and PI metal detectors. Moreover, it is not unusual for rockhounders to find surface examples of nickeline with its copper-green surface oxidation annabergite, and cobaltite displaying its pink-to-more infrequent reddish surface oxidation erythrite as depicted below. A wide variety of additional minerals can be collected from the mine dumps. These include more localized occurrences, for example, allargentum (silver antimonide), titanite (wedge-shaped, vitreous calcium titanium silicate formerly called sphene), native bismuth, chrysotile serpentine (asbestos), rutile (titanium oxide) and breithauptite (nickel antimonide), to more commonplace minerals such as sphalerite, arsenopyrite, chalcopyrite, bornite, galena, marcasite, iron pyrite, and so forth. A Final Word… In closing we should point out to interested readers that there has been a resurgence in active exploration for both diamonds and cobaltite minerals in the northeastern Ontario silverfields. The existence of diamonds has been widely known for years, and historically there has been a strong industrial demand for cobaltite for hardening steels and other alloys, paint, ceramic, and glass pigmentation, and in other various chemical manufacturing processes. Apparently now there is increased interest in cobaltite for the manufacture of batteries. Industrial demand notwithstanding, for many years cobaltite has also attracted hobbyists interested in recovering valuable crystals. I hope that both experienced mineral collectors and hobby newcomers have enjoyed reading about native silver and a few of the more prominent associated minerals in this area. Thanks for spending some time here, good luck with your rock and mineral collecting adventures, perhaps one day it will be our good luck to meet you in the field. Jim Hemmingway, October, 2019
  2. I was hiking in an area in central Indiana not really known for hotrocks. I went to check a creek island out for kicks and found out it is covered with rusty red rocks, and purple and pink rocks.The island is roughly 100 feet long and 20 feet wide and 4 feet high above the fast moving creek.It is jam packed with these rusty red rocks. Downstream is all a sheet of bedrock and small gravels and NONE of these rusty red rocks. I was told I could not pan, not so sure about detecting unless maybe my Falcon Gold Probe? How does one use this detector to check for ferrous and non- ferrous rocks exactly? I need to get some small gravels/dirt maybe and pan offsite. So, why is this island , or my so called Hot Rock island , like this? We usually only find red hematites and black sands and white gravels in Indiana creeks and not very many of them. But gold is usually found where the red stones are at and chunky black sands. -Tom V.
  3. “Robert Louis Desmarais is the only inhabitant of a Californian ghost town, Cerro Gordo, where he has been searching for a lost vein of silver for 22 years. A 70-year-old former high school teacher, Desmarais used to visit the remote spot in the school holidays to search for ore. But he eventually moved there full-time, to live away from the crowds "up in the mountains, under the stars". Cerro Gordo (Fat Hill in Spanish) was once the most fruitful silver mine in California. "It helped to build Los Angeles," Desmarais says. Convinced there is plenty of silver left, he descends 800ft with a chisel and hammer to "crack rocks and see what's behind them".” More story and photos at https://www.bbc.com/news/stories-49084230
  4. 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
  5. NASA’s Mars 2020 will land in Jezero Crater, pictured here. The image was taken by instruments on NASA’s Mars Reconnaissance Orbiter, which regularly takes images of potential landing sites for future missions. On ancient Mars, water carved channels and transported sediments to form fans and deltas within lake basins. Examination of spectral data acquired from orbit show that some of these sediments have minerals that indicate chemical alteration by water. The sediments contain clays and carbonates (courtesyNASA/JPL-Caltech/ASU/WUWT) Can't wait to wave a coil over those outwash gravel deposits. At least there's no BB's and rusty nails, could be a few metallic meteorites though - - - Luckily, I've got an old hot air balloon under the house somewhere - and warm winter woolies, so I'll see all you good people later. Wish me luck - - - I offered to take Reg along on the expedition - but he declined the invitation - can't for the life of me understand why? Not like him at all ;<)
  6. Though I don't prospect, I'd like to share this - HH and enjoy! https://www.nationalgeographic.com/science/2019/05/worlds-rarest-form-natural-gold-reveals-secrets/
  7. Many believe that the nugget gets rounded by it tumbling about. I have a large specimen that is flat on one side and I've always believed that it is that way because other objects passed over it as it stayed in place. This article confirms that for Blackwood, Australia and says: ‘A feature of many of the goldfields of Victoria was the finding of large masses of gold nuggets. They varied in size, and were not confined to any particular class of washdirt, nor with any regularity as to depth, but, from their disposition in restricted areas, certain belts can be regarded as typically nugget bearing. On account of the soft character of gold, nuggets of any size are always well rounded. This is due to the attrition of material passing over the nugget rather than rounded by rolling action. Many of the large nuggets had one side relatively flat, while the other was well rounded. Some of the nuggets were coated with oxides of manganese and iron; several had quartz attached to them, while a few were of ragged and roughly crystalline appearance.’ http://www.blackwoodpublishing.com/blackwood-eagle-nugget-found-1931/
  8. Hi all we are looking for information on different types of gold ground producing detectable gold / no gold panning I did not go around the whole forum but I see that there are prospectors from all over United States, New Zealand, Australia ?? the more information we have (precise) from different sources / better it will be ... so, among you who already find gold do you know the percentage of Fe2O3 and Fe3O4 on your hunting grounds if you have answers, please specify if the terrain is easy or difficult to find gold we are developing a testing ground with mineralized lands of different origins the goal being to have the widest possible range of difficulty to improve performance .. all information will be welcome Thanks !
  9. I posted this over in the meteorite forum, but after some research I wonder if the mystery rock I found is Limonite. I found this at a Fort Lauderdale beach yesterday, pretty far away from the water at a volleyball court. It was about 10 inches down in the sand, and my PI metal detector locked on to this pretty easily. I have a Pro Find 35 pinpointer, which makes a different sound for ferrous items, which it does on this rock. It weighs about 76 grams, seems unusually heavy for its size, and a magnet does stick to it. Before I send it anywhere for analysis, I was wondering if anyone here might have any thoughts? Possible Limonite?
  10. am not into geology ,,,,i dont know hard rock mining either .....what i know 5 types of lava .....what,, where and how would u look for placer in this lava or this area ??? ......this is in a gold rich area ....could a gold bug 2 find anything ?????? any information would be helpful thanks
  11. Another question via email, with personal references removed. I prefer to answer these on the forum so everyone gets the benefit of the answer plus others can offer their opinions also. "I am new to metal detecting and, your site here has really helped me out. I have a couple questions that maybe you can help me out with. What are some of the geologic indicators that you look for to determining where to prospect for nuggets? I try to study some of the geology maps but I could use some further pinpointing. I have also been looking at the National map of Surficial Mineralogy. Using the aster and minsat7 maps what are some of the indicators that may point you to higher gold bearing ground? Any help would be deeply appreciated. Could you point me to some old places where you have found gold? I'm not asking to be shown active patches. Just areas that you feel are worked out. I just want to see what gold bearing ground looks like. This would help me to start to learn the commonalities and characteristics of gold bearing grounds. Still looking for that first nugget! Thanks again for any info you can provide." My method is much simpler than that. I basically look for gold where gold has been found before. Think of it like fishing. If you want to go catch salmon you have two options. You can go to where people have caught salmon before - pretty good odds here. Or you can go where nobody has ever caught a salmon before. Very poor odds! So call it prospecting using history to determine where gold has been found before, and then getting as close as I can to those places. History and proximity. Finally, I may then employ geology to narrow that search in a given area if it turns out the gold is confined to certain rock types. The first place I normally turn as a rough guide to any new location in the U.S. is: Principal Gold Producing Districts Of The United States USGS Professional Paper 610 by A. H. Koschmann and M. H. Bergendahl - A description of the geology, mining history, and production of the major gold-mining districts in 21 states. This 1968 publication obviously lacks the latest production figures but it still is a great overview to where an individual prospector can look for gold in the United States. It is a 283 page pdf download so be patient. Pay particular attention to the listed references in the extensive bibliography for doing further research. You can download this here and find many more useful free books on this website at the Metal Detecting & Prospecting Library Principal Gold Producing Districts of the United States So just for fun let's say I want to go look for gold in New Mexico. The section on New Mexico starts on page 200 and here is a quick summary of the opening paragraphs: "The gold-producing districts of New Mexico are distributed in a northeastward-trending mineral belt of variable width that extends diagonally across the State, from Hidalgo County in the southwest corner to Colfax County along the north-central border. From 1848 through 1965 New Mexico is credited with a gold production of about 2,267,000 ounces; however, several million dollars worth of placer gold was mined prior to 1848. Mining in New Mexico began long before discoveries were made in any of the other Western States (Lindgren and others, 1910, p. 17-19; Jones, 1904, p. 8-20). The copper deposits at Santa Rita were known and mined late in the 18th century, and placer gold mining began as early as 1828 in the Ortiz Mountains south of Santa Fe. In 1839 placer deposits were discovered farther south along the foot of the San Pedro Mountains. The earliest lode mining, except the work at Santa Rita, dates back to 1833 when a gold-quartz vein was worked in the Ortiz Mountains. In 1865 placers and, soon afterward, quartz lodes were found in the White Mountains in Lincoln County; in 1866 placer deposits were discovered at Elizabethtown in Colfax County, and silver-lead deposits were discovered in the Magdalena Range in Socorro County. In 1877 placers and gold-quartz veins were found at Hillsboro, and in 1878 phenomenally rich silver ore was found at Lake Valley in Sierra County. The mineral belt of New Mexico is in mountainous terrain that lies between the Colorado Plateau on the northwest and the Great Plains on the east. It is a zone of crustal disturbance in which the rocks were folded and faulted and intruded by stocks, dikes, and laccoliths of monzonitic rocks. Deposits of copper, lead, zinc, gold, and silver occur locally throughout this belt. Some deposits of copper and gold are Precambrian in age, but most of the ore deposits are associated with Upper Cretaceous or Tertiary intrusive rocks. The gold placers were probably derived from the weathering of these deposits. In later Tertiary time lavas spread out over wide areas of the State, and fissures within these rocks were later mineralized. These fissure veins are rich in gold and silver, but in most places they are relatively poor in base metals. In New Mexico, 17 districts in 13 counties yielded more than 10,000 ounces of gold each through 1957 (fig.19). Figure 19 is a handy map showing us where you want to look in New Mexico and also where looking is probably a waste of time. Click for larger version Gold mining districts of New Mexico The map shows what the text said "The mineral belt of New Mexico is in mountainous terrain that lies between the Colorado Plateau on the northwest and the Great Plains on the east." Sticking to this area is going to be your best bet. Based just on this map I see two areas of general interest - the central northern area, and the southwestern corner of the state. The text mentions that placer deposits were discovered at Elizabethtown in Colfax County, and the map shows that as the Elizabethtown-Baldy mining district. Following along in the text we find this: "The placer deposits along Grouse and Humbug Gulches, tributaries of Moreno Creek, each yielded more than $1 million in placer gold and silver. Another $2 million worth of placer gold and silver was recovered from the valleys of Moreno and Willow Creeks (Anderson, 1957, p. 38-39), and some gold also came from the gravels along Ute Creek. Graton (in Lindgren and others, 1910, p. 93) estimated the placer production of the Elizabethtown-Baldy district prior to 1904 at $2.5 million, and C. W. Henderson (in U. S. Bureau of Mines, 1929, pt. 1, p. 7 40) estimated the production through 1929 at about $3 million (145,138 ounces). The total placer production through 1959 was about 146,980 ounces." The reference material from the passage above is in the back of the book and is where we can get real details. Google is our friend. This stuff used to take me lots of visits to libraries! Anderson, E. C., 1957, The metal resources of New Mexico and their economic features through 1954: New Mexico Bur. Mines and Mineral Resources Bull. 39, 183 p. Lindgren, Waldemar, Graton, L. C., and Gordon, C. H., 1910, The ore deposits of New Mexico: U.S. Geol. Survey Prof. Paper 68, 361 p. Henderson, C. W., 1932, Gold, silver, copper, lead, and zinc in New Mexico: U.S. Bur. Mines, Mineral Resources U.S., 1929, pt. 1, p. 729-759. That is more than enough, but let's also Google placer gold new mexico Lots of great links there, but two jump out: Placer Gold Deposits of New Mexico 1972 USGS Bulletin 1348 by Maureen G. Johnson Placer Gold Deposits in New Mexico by Virginia T. McLemore, New Mexico Bureau of Mines and Mineral Resources May 1994 Notice the source of the last one. Most states with much mining have a state agency involved that can be a good source of information and in this case it is the New Mexico Bureau of Mines and Mineral Resources. That last one is a real gem and contains this passage: "All known placer deposits in New Mexico occur in late Tertiary to Recent rocks and occur as alluvial-fan deposits, bench or terrace gravel deposits, river bars, stream deposits (alluvial deposits), or as residual placers formed directly on top of lode deposits typically derived from Proterozoic, Cretaceous, and Tertiary source rocks (eluvial deposits). During fluvial events, large volumes of sediment containing free gold and other particles are transported and deposited in relatively poorly sorted alluvial and stream deposits. The gold is concentrated by gravity in incised stream valleys and alluvial fans in deeply weathered highlands. Most placer gold deposits in New Mexico are found in streams or arroyos that drain gold-bearing lode deposits, typically as quartz veins. The lode deposits range in age from Proterozoic to Laramide to mid-Tertiary (Oligocene-Miocene) (Table 2). There are some alluvial deposits distal from any obvious source terrains (Table 2). Eluvial deposits are common in many districts; some of the larger deposits are in the Jicarilla district." So now we have a lifetime of ideas on where to go and a basic idea of the geology. And an even better map! Click for larger version. Placer gold deposits in New Mexico Let's look for specific site information. 1. Go to http://westernmininghistory.com/mines 2. Click on New Mexico Mines 3. Click on Colfax County Mines 4. Click on Elizabethtown - Baldy District Here you will find basic site information, references, and a zoomable map with alternate satellite view. An alternate site... 1. Go to https://thediggings.com/usa 2. Click on Browse All States 3. Click on New Mexico 4. Click on Browse All Counties 5. Click on Colfax At this point note you can browse mining claim information or deposit information. Researching mining claims, land ownership, etc. is another topic but here is one source of mining claim location information. For now.... 6. Click on Browse All Deposits or Use The Interactive Map 7. Click on Elizabeth - Baldy A little more detail than the previous site, including this note "SOME FAIRLY COARSE NUGGETS IN WILLOW, UTE, SOUTH PONIL CREEKS, GROUSE AND HAMBURG GULCHES, MORENO RIVER" One more... 1. Go to https://www.mindat.org/loc-3366.html 2. Way down at bottom click on New Mexico 3. Way down at bottom click on Colfax County From here you can dig into all kinds of specific site information but the navigation is a real mess. Have fun! Historic claim staking activity can be a clue. You can get the Big Picture by looking at Mine Claim Activity on Federal Lands for the period 1976 through 2010 OK, that really should have answered your question. As far as places I have been, they are nearly all in Alaska and can be found here. Now, I did all the above from scratch with no real prior information on New Mexico in about 2 hours. You can do the same for any state. However, finding where the gold is really is the easy part. The hardest part by far is finding out who controls the land and getting proper permission for access. In Alaska everything is covered by thick ground cover, so opportunities for metal detecting are strictly at creek level, and nearly always claimed. The process there is simple - find out who owns the claims and get permission for access. In most of the western U.S. there is far less or no ground cover, and so getting in the vicinity of and searching around or near mining claims without being on them is a far more viable option than in Alaska. Or you can try and get permission to access the properties. You still need to be able to track down property locations and owners however. For private property I subscribe to and use OnXMaps for my PC, Google Earth, iPad, and iPhone. It quickly maps private property and gives you access to tax roll information about the owners. Tracking down mining claims is easy in the big picture and harder in the details. The Diggings referenced before has interactive claims maps. I subscribe to Minecache for their Google Earth overlay. However, the most comprehensive source with the deepest repository of Land Ownership information is Land Matters. They have online claim mapping with direct links to claims owner information. Note that all online sources have a lag time between the actual staking of a claim on the ground and when it reaches the online systems, if ever. I say if ever because some claims exist solely at the county or state levels and there is no good way to find them short of visiting local recorder's offices or eyeballs on the ground. Prior thread on finding claims information. Finally, I am not an expert geologist by any means. This is just how I go about it, but any tips, hints, advice, or information anyone is willing to share on this thread are very welcome!!
  12. Do you ever question yourself, am I in an area that even has gold? It isn't always true, but if you see these indicators together you are probably not far from gold.
  13. I noted this on another forum but want to do so here too so here goes. How many of you have experience with pocket gold? I've pocket hunted a few places hopping around with a little luck, mostly CA Mother lode country and AZ. Here are some good reads for ya if'n you're not familiar with it. Anyone from the east do this, like Georgia or Virginia? I'l be visiting Virginia for a few weeks this year, would love to hear some local voices. Pocket Gold - Prospecting For The Source POCKET GOLD - LOCATING THE SOURCE Pocket Hunting for Gold » Pocket Hunting for Gold Pocket Gold Prospecting Pocket Gold Prospecting Mud Men: Pocket Miners of Southwest Oregon—Part I Mud Men: Pocket Miners of Southwest Oregon?Part I - ICMJ's Prospecting and Mining Journal
  14. I wanted to start this thread because in all the locations we all detect whether it is in western US or any where in the gold fields of Australia there is at least one spot that can stump all of us. This would be the spot that maybe we go and we know there has been good gold found there but for some reason we get skunked. This could be a spot that the geology is different than places we have success finding nuggets detecting. As we all know what's going on with the geology where gold is detectable is different everywhere. Knowing how the gold got to an area is very important for our success. Here is an example . In one area I detect Libby Creek the gold is on and in the bedrock as well as spread out thru all layers of gravel as though sprinkled from a salt shaker. I have this figured out. Another area you will not have much luck finding nuggets unless you are on the bedrock. Period. That is where the gold is in that area. The one exception to this in this area is hunting for specimens around lode mines. There is one place a friend of mine and myself have been going to detect for nuggets, each of us for a period of about 14 or 15 years and we both get skunked every time. I have held a 4 ounce nugget from this area found with a detector. So with this knowledge and knowing that three guys found 300 nuggets in this area in one summer, we keep going back. This is the eternal optimism of all of us who detect for nuggets. This area that stumps my friend and I is all granite the rock outcroppings the loose rocks on and in the ground are granite. The bedrock is granite, even the regolith on the bedrock is all granitic in make up. So I thought maybe if we all share info on the geology in each of our nemesis localities, perhaps someone out there has knowledge how to hunt these locals. I am not asking anyone to divulge the name and location of these areas, just the clues you have learned dealing with the geology in relation to the gold that led to success in similar sitiuations. Lets try putting our collective minds and knowledge together to help each of us. What is your nemesis spot. Maybe we all can help each other. Try to give all geological info that you know of too figure out the clues of where the gold might be hiding.
  15. Ive attached a lidar map of the main area i prospect. Id like to get peoples knee-jerk reactions on where they would swing a detector knowing large nuggets (they have generally been very crystalline with a few specimens found) have been found in the creek. So what would be your number 1, 2, and 3 spots to focus on. Ive detected around a good bit and have yet find anything outside of the creek, but i want to see if im missing something obvious. lol Search Area 1.pdf
  16. Ok, this is going to give away my lack of real-life gold hunting experience. I've heard two different responses to this question so I'm left a little confused and hoping someone can clear this up. My question is: In most cases would the larger pieces of gold travel less and be closer to the source and the smaller pieces travel further away? (this is what I would think would happen) On the few occasions if found patches I've found the larger bits were closer to the shedding reef but have sometimes experienced the complete opposite with some of my bigger finds a lot further down the slope. (maybe two different sheddings? ... they say that a reef at one time may have been a lot higher, so gold shed at different intervals may be in different spots) For those that have found patches what has been your observations? Cheers Jin
  17. I am going out on my first detecting trip I think I'll be using an xterra 705. The area I am interested in is south western idaho generlly around silver city the war eagle mine and a few other spots up there> I still have alot to do in terms of research and permission. I t looks promising , rugged and well who knows? Does anyone know if this is what you would call a mineralized soil area? I may drive on over to the Jordan valley area of oregon as well. any knowledge on this location? Thanks in advance.
  18. I have a question??? If gold is found on some beaches all over the world could it be found in sand under the tundra in Alaska????
  19. Hey Steve.... How ya doin with the earthquake swarm? http://www.rgj.com/story/news/2018/01/17/south-reno-earthquake-swarm-over-230-quakes-and-counting/1041466001/
  20. I have heard Dr. Erik Melchiorre give a talk on finding nuggets in Quartzsite that came from bacteria. He said he had been to Australia talking with someone there about it so this might be the group. It is an interesting discovery. http://www.abc.net.au/news/2018-01-22/how-your-old-phone-is-a-tiny-gold-mine/9330994 Mitchel
  21. Steve, I am curious if you have ever detected land slides, debris flows, translational slides, areas of mass wasting? And if you have did you find any nuggets.
  22. The USGS just released their latest Professional Paper 1802 Critical mineral resources of the United States–Economic and environmental geology and prospects for future supply. This thing is a monster! 862 pages and a 170 Mb download. That is a big download for a lot of people so we shrunk their bloated PDF down to 30 Mb. It's got all the stuff the bigger one does but the graphics are scaled down to web user size. You can download the full 862 page report directly from Land Matters. This huge report is fine in itself but to really understand what's in it we figured a map of all the locations would help. You can load up the Critical Minerals interactive Map right in your browser and study it along with your book. We've added the mines of the world as well as some basic base layers so you can compare the report locations to known historical and current mines. We'll be adding more features to that map soon. If you need to print out the book in it's original high resolution form you can find it at the USGS Publications Warehouse.
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