jasong

Gem silica is more rare and generally more valuable than chrysoprase, the next most vaulable chalcedony. It can sell for hundreds, or even thousands of dollars and ounce for prime, gem grade pieces. 2 years ago I discovered some old workings which I assume were initially copper prospects. A bit of research showed that an old gem chrysoprase mine from the 50's had been located a few miles away. I was unable to find the chrysoprase mine so I think that it was mislocated by authors of the paper, and I also think the owner and the authors misidentified the gem material, and the discovery I made is likely this mislocated "chrysoprase mine". The material at my discovery is what is called "gem silica" though. Chrysoprase gets it's green color from nickel. Gem silica gets it blue color from copper. I zapped the gem material with my XRF and it shows a healthy dose of copper and silicon, with minor impurities, meaning that my material is definitely gem silica. Gem silica has a hardness the same as quartz so it is resistant to scratches and good for jewelery. It resemebles chrysocolla which has similar colors (but less transparency) but chrysocolla only has a hardness of 2-4, meaning it makes a poor jewelery material as it can be damaged easily compared to gem silica with a hardness of 7, which is one reason why gem silica is valuable, aside from it's rarity. I removed this material with a rotary hammer and feathers and wedges. It causes it to fracture a bit more than I'd like. Next time I plan on taking my concrete saw out and trying to remove it in blocks. Much is fractured, so getting large, continuous pieces is difficult. Also, many parts of the vein end up with either iron or manganese impurities in it, causing a blackish tint and this reduces the quality according to traditional measures. Though, I think some of the blue/black pieces could be fashioned into some desirable jewelry as it is very unique. Interestingly, I did find some copper ore nearby that registered up to 150 ppm nickel. So, there may yet be a chrysoprase mine nearby for me to discover still. Either way, gem silica is a very rare and valuable material that few have heard of, so I thought I'd share a post on a bit of work I did at my mining claim to remove some samples for economic and scientific analysis.

Nice job, not very common to see nugget finds posted from back home! This is the area I first started prospecting, just by myself, and at the time had no idea there was nugget size gold out there since I didn't really talk to many people and mostly just found fines. I'd have probably been surprised like the guy in your story too!

I'm giving some serious thought to keeping the gold I find again now. It's starting to look potentially undervalued in light of inflation and unstable global occurences. I find it odd that inflation is so high yet gold still hasn't moved much, relatively speaking though. It's like there may be a different economic global order or something. Real estate was and kinda still is the best inflation hedge for the last 10 years. But if that collapses I wonder if it goes back to gold?

double post, sorry

A coil like explained in the patent Simon posted would mostly be beneficial for highly mineralized or highly variable ground. I think it mostly applies to saturable (FeO) ground, not conductive (salt) ground, but I might be missing something there. I'm not sure I see an immediate benefit of running one in mild ground. In fact, I can imagine a case where such a coil might actually miss or provide much weaker signals on nuggets if detected 90 degrees the wrong way, which have a very large difference between their radial and axial sizes (nail-like, or flake like) and so a person in mild ground may actually not choose to run such a coil and it would be a detriment to have this coil only on a detector. I might be missing something though. But it's that idea, along with the idea that as explained in the patent there is nothing stopping a person from running such a coil on a 4500/5000, that it sounds like it may be a standalone coil. However, people are right that Minelab has never been in the "coil business" and they certainly do take the opportunity to make as much $ as they can off products, and that may mean an entirely new detector. I'm not sure Simon's coil is actually the coil VicR posted about originally, so something additional may be in store there. I do agree it's about time for a nice, lightweight and more powerful GPZ though!

Proof of provenance is important here. What if there was another recent contender for #1 which does have proof? 🙂 🤐 Not just for history, but for valuation too.

Also, 2 or more coils stacked on top of each other could technically operate as a gradiometer. IE, not just detect the signal but detect the gradient of field decay and strength of a signal. Technically speaking, such ideas might conceivably used to differentiate targets by size and depth with signal processing.

I wonder if you'd technically even need a new machine though? This coil in their diagrams and most of their description is just a spiral wound mono coil, and so technically I suppose it could work on an old 5000. The difference is just how it's wound/molded, with the vertical section in the front/back or in the case of Fig 3, the dual level horizontal sections. The wiring is simply still just a mono though. The way the patent explains the physics behind it sounds like no special signal processing is required to gain the advantage of decrease saturation in the front/back while maintaining the advantage of the spiral windings being closer to the ground on the sides. That said, I'm sure modern signal processing in a new machine could probably squeeze even more benefit out of it, and well lets be honest, Minelab is going to squeeze as much $ as they can out of any product so that probably does mean a new machine and chipped coil, as you guessed. 🙂 They do make one brief mention of the idea that you could layer these windings (aka - 2+ coils in one), and that would definitely require a new detector to interpret and drive it.

That would be the largest raw nugget ever found in Arizona to my knowledge if it's true and can be proven/verified. Bud Guthrie's Lost Basin 70+ ouncer had a lot of quartz in it, so I'm not sure that counts? Can anyone think of one larger? Lots of 20-30 ouncers but that is where history kinda stops to my knowledge. I'm curious just for the historic record, if there is some kind of definite proof and/or verification it was definitely found in AZ other than word of mouth?

This would probably get more attention from prospectors if it was posted in the main forum instead of the Nokta/Makro forum. I only saw it because it showed up in the sidebar briefly and I saw the words "gold prospecting".

My last foray into Nokta resulted in 2 returned Fors Core's in a row. My 3rd one had issues too, and I just gave up on them entirely, that detector has sat in my closet since then, written off as a loss and learning lesson, and I paid no mind until I just saw this thread. Has their quality improved since their entry onto the scene originally? I haven't paid much attention to their products since then, until I saw this thread.

I'd use any brand that offered something better than what I have right now. Or something equal in quality but significantly cheaper. I'm 100% all for someone to give ML some competition. At this late stage in the game it's hard not to compare our feature requests to existing Minelab machines that almost all of us own or owned though. This is pretty much what I'd want at the $1500-$2000 price level. And if it had all of these, I might even sell my 6000. Just as light and ergonomic as the 6000 Noticeably better on small stuff than the 5000, while maintaining 5000 depth (preferably exceeding it) Backwards compatible with GPX coils Battery fast charging (like modern cell phones) USB C connections, not outdated or proprietary strange connections Quality rubberization on all wear points, carbon fiber shaft (any $1k+ detectors should have these features now IMO) A speaker, or something like the WM12 A good warranty or ability to get service that won't leave me sitting in the field for weeks with no working detector Fast modern processors and faster recovery time. The 6k/7k are slow in dense targets/trash, making it really hard to use them where you need to mentally discriminate targets A good, simple, quick control interface. Quick EMI cancel I'd exchange my 6000 out for a new N/M PI machine if it was less than half the price and about equal in features, even if not exactly up to par on the tiny bits that I don't care much for anyways. I don't need 0.04 grammers. but I do want to find 0.1 grammers at an inch or two still.

So far their gold detectors have been the only machines that utilized patented/protected coils, haven't they? I don't see a lot of reason to patent a VLF only coil. I do see a reason to patent the type of coil required for a machine I've been saying is technically possible to build for a decade now, with all our modern chips and signal processing capabilities: a PI/VLF hybrid machine. The idea being, you can modulate an alternating VLF-like signal right on top of each pulse, then process and analyze with Fourier analysis each of the signals separately. It'd probably need to be 2 coils in 1. If not 4 coils in 1. That's my "black swan" guess. It'd give you the ability to detect shallow small stuff, or ignore surface trash and detect just deep ones (aka, depth discrimination). Also technically speaking the ability to discriminate or even ID trash on a PI - at least to VLF normal depths, which honestly is probably all prospectors need since 75% of trash is usually shallow. I can dream anyways.

You used to be able to get small tracked hydraulic rotary rigs on Alibaba for like $15k that'd do 50-100ft, not sure what they cost now. They also make mini rotary rigs with skid steer mounts, I've been considering one of these for a few years. Drilling isn't really a great way to find deposits of mostly nuggety gold though if that's what you are after.

What are containers going for in SF and LA? They are like 2x normal price in Wyoming. Steel stock like angle and tubing is like 2 or 3x normal too. New normal with prices I guess. The only metal seemingly not going up is gold. Inflation hedge, what?

It must exist somewhere, I'm curious where exactly the federal government has granted states the right to manage federal minerals within their borders? Is this in FLPMA somewhere? For instance, where Arizona determines if rights of location do or don't exist on federal minerals and lands. Where do states have the authority or jurisdiction to make that decision? Article 4 of the US Constitution gives Congress sole authority over federal lands, Supreme Court has determined this power is "without limitation". Federal law can override state law if conflicts exist. Congress has given BLM (among other agencies) rights to manage federal minerals, lands, and other resources. These agencies I guess technically could delegate some of this management to states too. Something like this must have happened and is codified by either Congress or a federal agency somewhere otherwise how do the states have the right to grant or determine legitimacy of rights on federal lands and minerals where federal law has been complied with? Where is this written? I honestly don't know and it's not a loaded question, I'm just actually curious, haven't thought about it until now. Sec 3 of 1872 says you must comply with "State...regulations not in confict with said laws of US governing their possessory title". However, it doesn't grant the states the right to issue or deny federal title to federal minerals, since it's not state property. Actually, a state determining rights of location even if you've complied with Federal laws could in a way be read as to being in conflict with said laws of US governing possessory title. To be clear: I know the state can require you do this or that with a mining claim like require certain posts, or other specific requirements. What I'm wondering about is their authority to delegate wether rights over the federal minerals have or have not been acquired if these state requirements haven't been complied with.

This is something I've incidentally taken a great interest in recently as I believe this is what I'm seeing in an area I'm working in AZ. Anyone interested in looking at this chemical process further should check out the wiki on saprolites. This is usually what decomposing bedrocks are classified as, and they can even "produce" nuggets as well. This is called saprolitic gold, and is something almost never discussed or considered on prospecting forums. It can lay beneath laterite, which is sort of in between soil and rock, but in Arizona the laterite may be thin or missing. It's not just in the temperate/rainforested areas, but can be found in a lot of areas that are now deserts but were once much wetter due to climate change and tectonic drift, and so is something to watch out for a good reason to understand the local geology. Usually down here it's a reddish layer of soils followed by a whitish layer of less oxidized gravels, and then varying degrees of bedrock to saprolite. The saprolites themselves can "grow" nuggets. Some scientists propose a biologic mechanism, some propose a chemical mechanism, maybe it's both.

Not far from the truth. 😅 Stands for Plan of Operations. Small scale miners, exploration companies, etc generally try to avoid them because the delays can be excessive. They always (NOIs (Notice of Intent) can too depending on the office and scope of work) require full site surveys and reports (archaelogist, biologists, etc not just the geologist) plus a lot more bonding and oversight and a public comment period. You can get going with a NOI in 2 or 3 months sometimes, while a POO can take a year or longer.

I ran into that one too. Doing a NOI level operation you are allowed 1000 tons of disturbed or processed "ore" or similar verbiage. So I calculated based on that, and it was fine. Another BLM office decided the 1000 yards is any disturbed ground including road, and my road alone would have made it infeasible to do a NOI level and they required a full POO to be submitted. Yet in the same state I saw them allow another operation to disturb many times more than 1000 tons of ground total, including roads, and that very same office said nothing... Their opinions and facts often change based on what they had for breakfast, it seems anyways.

Since the BLM and sheriffs have shirked their law enforcement responsibilities regarding mineral trespass, and to be clear, mineral trespass is a criminal infraction (up to a felony depending on the law) which can and should be enforced - it's up to a claim owner to pursue civil litigation. A time consuming and costly process since law enforcement has failed miners in this respect. One should be very aware that in civil litigation you not only need to prove who the party is, but also the quantity of damages they caused. In other words, you can file a suit, prove there was a trespass, prove it was X person. And it won't mean anything in civil litigation if you can't prove what they took and what your compensation should be. So, it's not good enough just to get their picture, you need to document proof of exactly what they took and any other damages they caused. You cannot pursue criminal charges in civil litigation. You can seek damages. As mentioned by others, this is why people hire caretakers or just monitor their claims in person daily. Document any claim jumpers in the process, not just for ID but also to show what damages have occurred. It's also another in a long list of reasons why recreationalists shouldn't file mining claims, an instrument which Congress and the law intends specifically for commercial usage only - civil litigation is costly and time consuming, and loss of recreation is hard to value whereas loss of business is tangible.

You should be able to hit a 1 grammer of relatively sluggy gold like that at 6-7" with the 14x9 NFA and 4500 in mild ground. That was my go to coil on the 4500 for years. I'd almost say the 6x10 should hit it too. But it all really depends on your ground mineralization. What timing are you using and where do you have your stabilizer set? Threshold level? You should be able to run the 14x9 a click or two higher sensitivity than the max you can run the 6x10 if your ground is medium/hot. It's been so long since I've run the 4500 I can't remember which way the stabilizer goes, but if you set it so the threshold is too stable, you'll definitely lose depth quickly on the deeper ones. And if you are running in say Enhance vs Sharp, you'll also lose depth on those 1 grammers at depth. If you can't run in Sharp or Sensitive Extra at 11 or 12 gain and need to use something like Enhance instead, then I would say your ground is on the upper side of medium, if not hot. At least in terms of US ground.

Labs usually take between 50g to 150g of material for the actual assay. I send in about 500g-1kg samples usually. I believe they crush it all and mix it, and keep it for some time in case re-assays are ordered. Or you might use some leftover do metallic screening process on samples that assay over some threshold like 5g/ton in order to not miss high value results. Sampling is usually of 2 types - grab samples or chip samples. Grab samples can assay extremely high and be unrepresentative of an ore body. This is kind of what an XRF does. Thus, it should mostly be a qualitative measurement just like XRF, even though it's an actual assay. IE - more useful just to show if something is there or not, and how high in value it could potentially run in small, selective hand picked quantities. This sampling is often just picking up some good looking pieces of ore by hand/eye. If a project is only posting flashy grab sample assays...be wary! When small scale prospectors assay material, often this is all they are doing too. Chip sampling is different. I base my method loosely off my time with field geologists on my Gold Basin project. Basically, draw a line across an area of interest and hammer off chips semi-continuously over that entire interval into the sample bag. So, you are getting an overall representation of the gangue rock, many parts of the ore zone, and even some soil or caliche if they are in cracks and fall in the bag. You can do multiple sample intervals over the same line and get much different results - for instance if your line is 20ft wide then you could do a 3ft interval over just the vein, and two 3ft intervals over each side of the wall rock, and a 20ft interval over the whole thing. So, you can have assays that end up representing any part of your zone of interest individually, or any combination of them. When doing this, it's important to ignore what you are hammering and just take it all in, the whole kit n kaboodle whatever it may be. No selective bias at all. This is important today because many projects are looking at bulk open pit mining, so if your gangue material is holding something like a consistent 0.5g/ton gold in addition to the primary vein/ore, well then it might be economically feasible today whereas it wasn't in the past. It's also similar to core sampling, where instead of spray painting a line to sample across, you are assaying different intervals of the core where the drill hole itself is your sample line. My terminology here probably isn't 100% correct, but you get the idea of the process more or less.

You are probably right. I haven't seen that TV show, but I've seen similar results. I own a property that in fact does have iridium (as well as all 5 other PGE's). I decided to search for the source since they show up in AAS in the black sands. I thought I found the source, my XRF showed both Ir and Pt. I sent rocks in for assay, and they confirmed PGE's in the host rock. They confirmed it in...well...suspiciously similar quantities as my XRF showed, even though they said they were not using XRF for assay. I ended up buying my own assaying equipment and teaching myself to assay because I didn't trust these lab results. And I was unable to reproduce the gold results from either lab after a month of trying and probably 30 or 40 attempts. Well, many other things happened. And long story short - I think that maybe 2 labs are actually using (and misinterpreting) XRF results either in the finish, or just as a total shortcut for their PGE assays, and I think maybe for their gold assays as well. I wasted a ton of time and money on that. I finally spent the money and waited the 2 months to send my samples off to the same lab that Barrick, Newmont, etc are using in Nevada, and it confirmed my suspicions. The last lab was expensive. But they had proper chain of custody and complete documentation for each step of the assaying process, plus they had lab controls that I could go back and check. And I will NEVER. NEVER. use a cheap lab again, only professional labs for assays for me from now on. Expensive lesson I learned. I won't ever use XRF as a substitute for a real assay. I just use it as a quick field tool to gather data and samples to send in to a proper assay lab.

I have a Oxford Xmet 7500, it was a demo unit for a dealer I bought used so it comes with every method they offered at the time. I paid $15k for it, which was quite a deal given the amount of methods it came with. It doesn't have a Geochem method, but it does have a specific method for cobalt that I believe has an algorithm to differentiate from the iron peaks. The problem is the cobalt method doesn't have as many elements as the mining or soil methods installed, so that's why I want to send it back to the factory for recalibration for soils/rocks specific to what I'm looking for. For instance to be able to have high accuracy for cobalt in gravels/soil with high iron content too. The problem is...what I'm looking for always changes. 😀 I can definitely see "bleedthrough" when looking at gold with other elements with similar peaks too, Hg, Pt, etc. It's a Rhodium anode so I thought it'd be better for gold but it's still not accurate enough for me to take gold readings seriously unless it's like maybe 1000ppm or higher. But at that point I could probably see gold in ore with a loupe and bare eye, so... All of this kind of stuff is why I only use the XRF specifically qualitatively and not quantitively myself. For instance, with cobalt, if it's under like 50-100ppm I'll probably still ignore it as potentially spurious. And higher readings I don't really take the numbers specifically, I just look at it more like a "present/not present" element indicator.

Haha thanks, I love that side by side. I got a 50w solar panel up top, a lifepo battery behind the seat, inverter, mounts for many detectors, rock hammers, picks, pry bars, shovels, claim stakes, and everything else a prospector would need for an expedition! Got an ammo can just for shackles, slings, and other stuff just to pull boulders (or pull myself out of a ditch). Another ammo can just for chisels, hand scopes, streak plates, sample bags, hardness tester picks, etc. It's a modern prospecting chuck wagon! Definitely wasn't me who found the nugget. 🙂 I can wish though... If I had to guess I would guess Mexico right now. But it definitely could be an AZ lump as the two places have some very similar looking gold.