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Quick, not sure if you’ve swung a GPZ 7000 with the Hip Stick on extended hours and combined days on a hunt! The Hip Stick does pull on your Shoulder. Doc’s DALAS transfers that stress to the Waist Line Clip. As a beat up old guy, I’m looking forward for that Slow Boat! Rick

So for 9 yrs you've been holding out and making us old guys wear our bodies down, run out of steam and then quit the hunt early. You've probably been using it the whole time, until your friends called you out "extortion ". You had no choice then, so the cat is out of the bag. One of my biggest issues with the GPZ-7000, weight....and that attempt at their exoskeleton harness. Doc, Minelab just needs to put you on their payroll so we get the right fit, feel, tools and accessories from the get-go. Now, I'm excited about swinging that Beasty 7 again... when I have Dalas. I'm sure it's not going to cost $1000 like those coils so many folks purchased, just so they could swinging the 7 again. Looking forward to it. BTW, when Michelle and I come visit Vegas, we'll be in the pool, your pool.

Packing an .06, shells, a 7000 and my recovered nuggets all day long? I think I'd rather get et by a bear.

We live up high on a hillside in a canyon town in So. Cal. My wife has cultivated unbelievable gardens; we live in beauty. I got to terrace the hillsides on our property when I was younger, but that had to stop - yup back problems. But now, years later, I still go out and detect with my 7000, I've strengthened my back and know what not to do. But I always wear a back brace when I sweep, rake or mop. Eight years ago, my wife came with me for two nights camping up in the Mother Lode in breathtakingly beautiful country. As we were leaving I heard her say to herself "okay I've done that." Now, I often say her idea of being in the great outdoors is cracking the window open in our hotel room. Funny thread Doc.

Thanks Phrunt. I wish I could run in normal. The difference is quite pronounced but you can only do what you can do. I forgot to mention that the sensitivity was knocked back to about 15 after starting in 18. The variation in mineralisation was quite pronounced over a relatively short distance and made a significant difference in how both machines coped with the ground. As always, the 7000 in the morning is a bit like me, we both need a coffee and a bit of time to warm up before we can operate properly.

Hi Folks, Just thought I’d give a bit of feedback on the 8” X Coil that I pinned to the 7000. Yesterday was its maiden voyage into our local gold country and Joe and I were keen to see how it performed in the field. We decided to go back to a creek bed that was mainly dry to see if we could scratch out a few targets and do some comparison work between this coil and the 10x5 Coiltek that was swinging on the end of Joes 6000. After burying a few targets the day before and running both machines over them, we already had a bit of an idea as to how it would perform but nothing beats detecting in a real situation to see how a machine/ coil combination works. I purchased this coil so that I could give my daughter the 6000 when she comes out detecting and I could then use the zed with a small coil to work through old workings or around rock bars. The 12” ZSearch is a great coil but is a bit too large for this type of work (especially with the thick undergrowth that now exists in our gold fields.) The first thing I noticed was the weight of the coil. It is reasonably heavy for its size. It is of a similar weight to the 12” coil and I’m guessing it is full to the brim with wire. On the Zed it is well balanced and it swings nicely with minimal effort. External build quality looks quite good and it appears that it should be able to cope with a good workout. Joe and I decided to walk the gully well past where we detected on the last trip and see if there was any gold present higher upstream. The first issue with the X Coil is that it’s not waterproof so I was restricted to dry rock bars and banks. Joe was able to do the shallow pools and submerged bars to ensure that we had all bases covered. The area where we started to detect was highly mineralised with hot rocks and noisy ground upsetting both machines. Threshold was stable but false signals due to the ground were an issue until we moved downstream. Apart from a couple of bits of rubbish, nothing of any real interest turned up. We slowly worked our way down stream until we got to an area that had produced some gold on a previous trip. The zed was behaving a bit like a hyperactive kid that had been fed a handful of red lollies. In other words, it was running like a 6000. In a funny, twisted sort of way, it was a good feeling as I knew the coil was right on the edge and was super sensitive. As we had detected this area before, we knew that we had to make a bigger effort to reach difficult spots, move a few rocks and fallen vegetation etc to see if we could uncover something of interest. Joe started detecting a yellow clay bank as it was a good trap for gold during a flood. I decided to try an steep area that was well above the stream bed where there was evidence of past working by the old timers. At the base of a cliff face, I noticed a couple of undercut areas which were gouged out by last years floods. I was able to get my detector coil into one of these holes by lying flat on the ground and reaching forward through some flood debris in order to swing the detector. A very faint moan hit the headphones which wasn’t surprising at all as the hole had a lot of red mineralised soil in the cavity. It sounded just like every other broad, false signal that I’d been getting during the morning from similar material but as per usual, a check was in order. The pick was used to drag out about 6” of this dirt. It was soft and not compacted in any way which indicated it was recently deposited. When the detector was placed back into the hole, the signal had sharpened up and I knew that I had something metallic. I wish now that I’d called Joe over before any material was moved so that we could have done a bit of a comparison between the machines. My gut feeling is that the 6 would not have heard anything at all but we will never know for sure. Eventually I dragged out a nice little nugget of about 3/4 gram. When I ran the machine over the spoils, a signal was detected and another small piece was recovered. Joe picked up a couple of small pieces that were barely a signal so he didn’t call me over to check. You know the ones I’m talking about. “Is that a signal?” One small scratch with the pick and then it screams at you. The typical 6000 small gold scenario. I started detecting a high vertical bank that had washed away badly last year. When I placed the coil under a tree root, the machine screamed loudly in protest. I knew it had to be junk or a shallow piece of gold. One careful scrape with the pick and it fell into the scoop. Couldn’t believe my luck when a nice little half grammer winked at me. No skill in that one. A kids detector could have found it. But in saying that, no one had put a coil in that location before so I took it with a smile. After a brief stop for lunch, we continued to slowly move towards our starting point. I picked up the zed and took one step forward before getting a nice little double “bleep”. It was pointless getting the 6000 to run over that target as it was quite a shallow, dig me signal. Turned out to be a 0.08g piece at a depth of about 1.5”. It was good to see that the coil could pick up bits of fluff with ease. I decided to follow Joe and work the same clay bank that he had just detected to see if there was a deeper target to find. Normally, that wouldn’t be a good idea as Joe is very good on the detector and rarely leaves even a scrap for his mate. About 3 metres from where I picked up the little nugget, I ran the X Coil over some vegetation that had been partially washed away by flood water. I could see the clay bank was about 5 inches under the exposed roots of a small bush. To my surprise, I picked up a signal when the coil passed over the area. The vegetation was pulled out of the way and this is what I saw: Before it was moved, I called Joe over for a look. It was a beautiful little sunbaker. Joe passed his coil over the top of the nugget and lost the signal at about 4”. The process was repeated with the X Coil. It still gave a faint signal at about 5.5”. That was the first bit of information that demonstrated some of the X Coils potential. The piece weighed in at 0.095 grams which is pretty small. Joe picked up a couple of micro bits on a bank during our walk towards the car. He finally found a slight but repeatable signal that he thought might be a good test for the new coil. He put back the scrape of material that the pick had removed and the X Coil was then directed across the area. In all honesty, there was very little evidence of a signal at all. There may have been something but under normal detecting conditions, it would not have stopped me. When the scrape material was removed, a faint signal was heard. It ended up being a really small piece of shot and showed how good the 10x5 coil attached to the 6000 is when the gold size gets really small. It was a day that was hard work and didn’t prove anything much at all except that the X Coil is capable of finding small gold at good depth. Will it compete with the 6000? In some situations depending on gold size and depth, it may do well. In others where the gold is really small and shallow, the situation may be different. From yesterdays trip I could say with confidence that the zed/ X Coil combination is one that I will use in many of our future adventures. Will try updating comparisons as we test over time. Here is a pic of the gold that it found on its first outing. And our tally for the day.

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I don't like their marketing charts at all, they're manipulative, they don't declare which coil they 5000 is using, nor do they mention changing coils on it would change the results, they make out that the 5000 performance doesn't change and the result it had in their testing are the final results. The same goes for the 7000 although that's more satisfactory as the aftermarket coils for it are not official products. I'd rather they not did these performance charts for marketing. I'm sure when the new detector comes along it's chart will demonstrate it's better than what currently exists, in the form where the current models are lacking intentionally to make the new model look better. 🙂 I'd rather they just verbalized it saying what's improved, how it's improved and why they improved it. For example, for the 6000 they could say they've improved performance on small gold and specimen gold, along with lightening up the detector and improving its resistance to EMI over the existing GPX series. This would all be very truthful and stuff any owner of it would be able to clearly see as beneficial when they buy it. They could use marketing to bling it up and add a lot more benefits too. As for testing, it seems not long after release JP at least was commenting on the issue, the more the end users were pointing it out the more obvious it became there was something wrong. Minelab likely said they think there might be an audio feedback loop going on and they're investigating it, still took a long time to resolve, but we are all happy they did. Some days mine ran a dream, the next I was being punished pushing noise cancel all the time, factory resetting over and over again or just turning it off, waiting 5 minutes and turning it on with a factory reset to calm it down. The fact it had good days makes you think perhaps it's just environmental EMI and a detector running on edge, but you could replicate the same problems in very low sensitivity. It turned out it was poorly shielded inductors so changing inductors to better ones resolved it, I believe due to this every model with the old inductors is affected to some degree, now all new ones use the new brand inductor. If the testers spent their time in headphones, they likely wouldn't notice it as it was nowhere near as bad with headphones, and who would think by using a speaker you would change the detectors stability, it probably wasn't tested on speaker much, the speakers also not loud enough for noisy environments, I hunt near rivers a lot, can never use the speaker, far too quiet. They should have had a GM1000 speaker in it. I don't think Minelab will make a similar mistake in the future, the best people to test a product for a fault like this is the engineers working on it, not a detectorist. How is a detector user going to know what's normal or not when it comes to wild behaviour, yes, they can point out it was noisy or seemed to have unusual EMI issues on certain days, but the engineer would be the one that would know something is truly up if they were using it when it happened. It's an engineering issue, not likely a tester issue. The engineers missed the fault.

It’s been doable for ages and suggested for longer. White’s could have stuck a MXT and TDI SL circuit boards in one box and switched between them, and still been lighter than a GPZ 7000. The main thing would be designing a coil that could run well in both PI mode and VLF mode. Not a huge hurdle really as a PI can run almost any configuration - it’s the VLF side that’s pickier so design for that as the priority. Now obviously an MXT board and a TDI SL board today would be way, way smaller than what Whites made. Think more like Manticore plus AlgoForce E1500 together in a single package. Both could easily fit in something about the size of an Axiom. As you say, two separate detectors in one housing with ability to switch between the two. Obvious idea, brought up many times. So why has nobody done it? Lack of outside the box thinking at the majors that has them thinking this or that, but not both. At one time it was just a too klunky option really, but with today’s smaller circuit boards and more powerful batteries much more feasible.

Most certainly is LITE. The detector with the small coil is lite'er and the cost of the unit itself is lite'er on the pocket. Actually, one of the blessing of the Axiom is how much lite'er it is when compared to the competition and then most certainly lite'er on the wallet vs those others. Did I tell you I found more gold with the Axiom in 2022 and 2023 than I did with my GPX-6000 and GPZ-7000 combined. I won't even mention what a couple of my Field Staff did. Let's just say, many folks assume and wear blinders. I realized my blinder mistake many years ago, so now I keep an open mind and let the results dictate my preference. In no way am I saying the Axiom will always outperform my GPZ, but with the added features, it sure shines through in many applications. Can't argue results, that's for sure.

Hello All, I'm listing this for a friend that does not have access to the internet. He purchased a new GPZ 7000 about 2 years ago, but never was able to get it into the field. He put the unit together, but never was able to get it out of the house. If you have any interest, please contact Brian at 520-904-9025 (Southern Arizona area) to chat with him about it and pricing. I'm sure he's willing to make someone a deal, but remember he purchased it at $8000+. Thanks! Rob

Thank you Gerry & Phrunt. While the 6000 has been a shambles & a frustration for many, I somehow have not had issues with mine. Touch wood. We do know who the tester were Gerry. Maybe they were just not aware of the issues at that time or ML did ignore them. JP did promote it as being highly strung & on the edge due to the nature of the beast & its heightened sensitivity & jittery nature therefore etc etc. I am not a Minelab basher as such as I have loved all my ML machines. I just don't like their business model antics in controlling their market share/domination & take my hat off to the likes of X coils who developed a work around for the chip on the 7000 & have obviously made a heap of very good coils that has called ML out on their say so that a 10" coil wasn't physically possible to make with the amount of wire winding required in the small space of a 10" coil. Despite them saying they would make a 10" coil. X coils pumped out not only a 10" but also an 8" coil & many more. The CC's being from what I have seen a huge hit. Left egg on ML's face & has basically called them out as liars. @Phrunt. I find it interesting that the bit of gold you did find while detecting with Mitchel was found with the 6000 & an aftermarket coil despite your favoritism being with the 7000 & 8" X coil that found you nothing. While you showed that video of your patch clean up at the area you took Mitchel too with the 7000 & 8" X coil. Who is to say that the 6000 wouldn't have found those with the 10x5 Goldhawk coil in among those thyme bushes? I have to admit that the 15" CC seems very impressive. D4G

I have no issues with Simon and many others showing frustration with the GPX-6000, Minelab earned it. Why did not the original Field Testers notify Minelab of the issues? Maybe they did and Minelab turned a cheek, we will never know. This I know for a fact. I complained about the issues to Minelab USA and was lied to. I also sent an email and to this day have yet to get a reply. Not sure if the folks at Minelab USA has any say anymore, but they did back in the 90's when I first started promoting Minelab. Now you might call me a sour Minelab Dealer, but at the same time, I promote the heck out of their detectors and show more pics of gold success than most other dealers who sell the same product. I love their technologies and performances. I also appreciate the 3 year warranty as for many years it was only 2 yrs. I don't appreciate their strategies of price points. I say this as I have been one trying to sell their detectors for near 30 yrs. Why not offer the same detectors at 1/2 the price (still more than the competition) and sell twice as many. Then come out with new versions every 3 to 4 yrs (like they did back in the early days) instead of waiting 9 years (based on GPZ-7000). Back to the next new big detector from Minelab. It will happen and probably as Lunk mentioned (during the May 2025 Worldwide Conference. What do I hope for? A detector with GPZ-7000 depth on solid gold, with the lighter coils, size and ergonomics of a GPX-6000 and also have Sensitivity of specimen gold, Discrimination and Fine Tuning that the Axiom has and then price this package at $4999 US. I would think gold could be around $2500 US an oz and we could sell twice as many detectors. Only time will tell.

Sad you got a dud & also lost 12 months of critical detecting time. Especially as your friend got one quite early as we both got one about the same time as we were communicating a bit at that time. He got 12 months on you & most likely on the ground you have been doing as well. That is my point with the "early bird gets the worm" comment in my earlier post. Also that ML honour their warranties so any issues they will sort out. From memory you were so frustrated with your dud out of the box that you bashed it & it came to life. Whether that was good or bad & that maybe you should have sent it back under warranty, you will never know. I guess by going public that you bashed it would void your warranty anyway. Not everybody in detecting world is evil or has evil intent. That is most likely not the right way to word it but I am referring to X coils (the non evil party) & again those that went down that path, & obviously as it turned out against Minelabs wishes & many others, the early bird again got the worm. I am one that didn't go down that path but most definitely see its benefits. Despite all the fallout from that saga if it wasn't for X coils pushing minelabs hand we wouldn't have the NF Z search coils that so many go on about being better than the ML coils for the 7000. Any innervation, no matter who or where it comes from, has to benefit us detector/coil users. I think we are now all up to speed on Minelabs business model of mining the miners & ham stringing their detector/coil combinations in regards to aftermarket coils that don't get their approval.... for obvious financial reasons to them & their detector sales. Competition is good & are other manufacturers now going to get a good slice of the pie or is it too late with gold getting harder to find by the day. Despite its high price at the moment, the glory days are over & we are just struggling along on the vapour of an oily rag. D4G

Garrett just informed us happy folks in USA, the proven Axiom is now available in the US in the same LITE package they have been offering in Australia. I know this detector well as many of you seen the posts of Success picks my Field Staff/I have shared the last year. Yes I feel it's the best priced high performance PI detector on the market in the USA at this time. Yes it has features my GPX-6000 and GPZ-7000 do not. If you don't think it can find small gold, sorry you are mistaken. It's incredible at the small stuff, just ask Steve H or Lunk. Now's your chance to get this detector for $1000 less. Don't forget, since I am a VET myself, I offer the full 15% to those Veteran customers, as you earned it. Veterans supporting Veterans. Semper Fi. Picks of Success (below) when we were testing different prototypes. Happy Hunting. Gerry

The pulse induction detectors currently manufactured and listed on Minelab's website are the SDC2300, GPX 5000 and GPX 6000. There is also the GPZ 7000 but it uses what Minelab labels ZVT=zero voltage transmission instead of pulse induction or induction balance tech.

I was always interested to see the differences with a new model 19kHz Fisher detector, they seem to slip in updates to firmware over time as they work things out, and do other changes to enhance performance and the 19kHz Fishers are really good detectors. With my Gold Bug Pro's being quite old now, I wanted to compare them to a newer model and see if they had fixed the problems I knew about with mine, and thankfully they have. My Bugs were bought when I first started detecting, I bought them at a Fisher stockist in Australia as NZ's dealer had no stock and went out of business shortly after, I did manage to get my GBP 10x5" Coil from him before he went down. The trio What I noticed immediately was the Gold Bug Pro's ran at 100% gain more stable than the F19, at first I was disappointed by this, especially when the larger Detech Ultimate 13" coil went on the F19 it was noticeable how much more unstable the detector was, 90% gain on the F19 was as stable as 100% gain on the GBP. This is the coil I noticed it most on, the smaller Nel snake both ran at 100% gain fine. With a bit of further testing I've established the F19 has a higher overall gain than the GBP's, this gives increased target sensitivity and depth, so, as a prospecting machine the F19 (new model) is better than my Gold Bug Pro's (many years old models) When the GBP is running at 100% gain with the Nel Snake, the F19 with the same coil at 100% gain slightly betters its performance on tiny gold. These were my test nuggets for comparison. I also put it up against a much higher performance detector on small gold, the Gold Bug 2, while the audio on the GB2 is much louder on the targets, the F19 was able to give near equal performance as the nuggets were bigger, and the smaller ones the GB2 did better, but the difference wasn't as dramatic as I was expecting. I retired my GBP's from prospecting detectors a long time ago, but it was a pleasant surprise to see they still do pretty well, especially with the Snake, it gave a significant boost over the Nel Sharpshooter (Cors Fortune) coil, and of course the 10x5" stock coil on small gold. The other problem I had with my Gold Bug Pro's was the 99% silver large coin wrap around to iron issue that the Gold Bug Pro had, I am not sure if they have fixed this in newer models but it was a problem on both of my Gold Bug Pros. Here is a video of the problem I took when I first discovered it. I was able to fix the problem with my Gold Bug Pro's by opening them up and adjusting a POT, I was careful when doing so, it was ever the slightest turn to get the silver wrap around to go away, I also tested using a ferrite and small lead targets to ensure they were falling into the right place before and after doing the adjustment. Here is the same Bug once I'd adjusted the POT on a few different large silver coins. Working well now. I found this comment on a Youtube video about the F19 and silver coins by someone, they indicated Fisher had fixed up the silver coin problem on the F19, so I tested it out, and indeed it is fixed. My UK 99% silver crown test coin now comes up in a good spot, this was with the same Snake coil. I'm going to now re-tweak my GBP's so they come up the same numbers as the F19 by adjusting the POT again, as I'm sure Fisher worked out a better spot to put it than I have, mine was guess work, they would have the proper knowledge to adjust it correctly for best results. Now the odd thing is when Fisher compare the two on their website they say this They completely neglect that the F19 has better notching, a backlight, volume control and this new higher sensitivity than the Bug, at least the Bugs I have as the big differences between it and the Bug. The other odd thing is in their specifications for it on their website they say it takes two AA batteries, buzzzz wrong! It takes a 9v. Fisher really needs to get their act together, you can't even download the GBP or F19 manual from their website, dead links, and to give incorrect information about models is just wrong, how could they think it takes 2 AA batteries? Some bad cut and paste work going on no doubt. So, as it stands, unless the GBP has improved since I bought mine someone would be crazy to pay for a GBP, especially if it still costs more like it historically has just for the name, as the F19 is significantly better, I think I may even start using it. By the way, you can check your Bug firmware version by having it in disc mode, holding down the pinpoint/GG button when you fire it up, mine both come up version 4, and to check it on the F19 you hold down the pinpoint button while in disc mode when you turn it on, not the menu button, and my F19 is version 3. I wish we could see a changelog of the firmware updates for both detectors.

I did a rough count on the most used/favorite coils and added them up minus the single numbers, thanks everyone for sharing your thoughts and experiences. Here’s what I came up with: GPZ-7000 has 5 for NF 12” Zsearch 3 for OEM 14x13” 2 each for X-coils 8” 2 each for X-coils 15”CC GPX-6000 has 6 for Coiltek 10x5” Goldhawk 3 for 11” OEM 2 for NF 12x7” Exceed GPX-5000 has 5 for 15” Evo Spiral 4 for 14x9” Evo Spiral 3 for 12” Evo Spiral 2 for 19” Evo Spiral SDC-2300 has 2 for Coiltek 11” Mono Equinox series has 3 for the 6” coil Gold Bug 2 has 3 for the 6.5” CC Axiom seems to favor the 11x7” coils from my experience.

As I recall the QED was sold with a couple of those ferrite cores to attach to the coil cable next to where it connected into its control box. Maybe phrunt when he owned a QED had found if the ferrite core made any difference when attached to the coil cable?

Don't be so sure Steve.... from what I hear, this isn't so far from reality, Hopefully the 20% more depth is on all sizes and shapes of gold and not just a chart claiming better depth. I would still like to see the actual Star Chart and GPZ 40% deeper testing site details on how they came to these conclusions. I am also worried that the next release will have proprietary coil options that do not cover all gold types or sizes until you upgrade to the flagship version, even the 7000 never allowed us to buy any approved coils under 12”. In the end, I guess Minelab still controls the market and I’ll just have to conform and buy whatever performance improvements help me be able to find more targets.

yea, if you're in ground the EVO's on the GPX 4500 were noisy I think you would find the same with the spirals and it's the reason X-coil make standard bundle DOD coils too like the Z-search coils, the sensitivity would be the main benefit other than being able to pick the size coil you really want to use rather than the Z-search which is almost the same size as the stock coil, if you don't need that it's a pointless exercise. As Lesgold was pointing out he was able to find gold deeper with the 12" than the 14x13", that makes sense as at the right size gold there is always a cross over a smaller coil will do better than a bigger one on some gold, even if it's only slightly smaller, pretty hard to find that sweet spot in the wild but I guess they were able to do that with various target checking between the two. As we all know different ground changes results. I cruise around in HY/Normal with a sensitivity of 19, I can easily run 20 with any of the X-coils so I'm one that benefits a lot from the extra sensitivity as it doesn't change my stability at all and we are a place that tiny gold is the gold you're going to find 99% of the time, but I find 19 sensitivity has a more stable threshold which I like and going that extra notch to 20 doesn't seem to provide anything much more than a little bit more unstable threshold. In saying that, the 7000's a dream even at 20 to run for its stability over the 6000. I was just using the 7 with 8" yesterday after not using it for a few months as I wanted to get my money's worth out of the 6000 as if it plays up out of warranty, I'm just getting rid of it, I may even offload it before the warranty runs out as I don't have a lot of faith in it being a long lasting detector, what a smooth nice running detector the GPZ is by comparison, I'd forgotten how smooth it runs compared to the 6000, in fact it was just purring along perfectly.

Any time you place ferrite near a pancake coil it causes the flux lines to bend more. This is why mineralized ground reduces depth, it increases the flux curvature and reduces flux density at depth. Placing a ferrite shell on top of the coil certainly does what you envision (reduces the top-side field); at the same time it increases the bottom-side flux density very close to the coil but this advantage is quickly lost and at depth the flux density is reduced. Here is an FEM plot: Here is the same coil with the ferrite set to air: It's possible the ferrite-shelled coil would be good for shallow tiny nugget detection. Another (lighter) possibility is to design an anti-Helmholtz coil, where an anti-phased bucking coil placed just above the TX coil to "focus" the field downward: Unfortunately it tends to also reduce flux density at depth compared to just a single TX coil. .

I'm envisioning the opposite of a ferrite core, more like an exterior casing to concentrate flux such that the amount of magnetic field energy is maximized towards the ground and minimized towards open air. Since half of the field of a coil radiates upwards and thus is not particularly useful for detecting, it seems to make sense to put it where it's more useful - if possible? Here is a cutaway diagram. Would this not have any benefit, at least for near surface flux density concentration? At the field strengths of PI machines I'd guess something like fairly thin 24 gauge steel would be more than enough, saturation is probably ok since the goal would just be some improvement, not capturing all the upwards flux. Is there a way to use that other half of the "wasted" (using that term loosely) magnetic field energy more usefully downwards if this doesn't work? Sort of like the idea behind a Halbach Array, except whatever the EM version would be? Weight alone doesn't have to be a deal breaker. For instance if a hypothetical 12" coil with flux shaping components weighed the same as a 20" standard coil, can it be made to obtain similar depths? If so, then it'd be worth it due to maneuverability with all other things being equal.

A very interesting thread. Jason: No, adding ferrite won't help, it'll just make the coil heavy. The only exception is in a pinpointer where a ferrite rod is used to concentrate the field. This works well in a PI or energy theft pinpointer which use a mono coil. When you use an IB coil the RX must be air-cored so, ferinstance, the White's TRX has the TX coil wound on a ferrite rod but the RX coil is on a plastic bobbin. If this concept were used in a regular detector, you would have a big long ferrite for the TX coil with the RX underneath, so the coil is 8" thick and weighs 20 lbs. Chet: Have you ever tried using FEM software?

We all know Minelab are always working on their next generation detectors, be they coin/relic/gold or dedicated gold, as Gerry mentioned elsewhere. I'm guessing that the next GPZ detector will be revealed at the upcoming Minelab dealer conference in Oz, May of 2025. I believe that to be a reasonable prediction, as the 7000 is so long in the tooth now, and Minelab's next flagship gold detector is long overdue.