VLF vs PI detectors

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VLF vs PI detectors

Post  hotrock on Thu Jan 19, 2012 5:53 am

l'm new to this, so the main difference between the VLF and the Pi detectors such as the minelab SD's and GPX's is that they handle the ground minerialisation alot better so you don't get a whole lot of false signals like you would with a VLF detector. Those that have used both a VLF and PI detector how much better do you find the PI machine ? do you find alot more gold and is detecting alot more enjoyable because you are not digging on false signals anymore? what VLF detector handles minerialsiation the best? is there a VLF machine that handles the mnerialsation almost as good as a PI?

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Re: VLF vs PI detectors

Post  Guest on Thu Jan 19, 2012 8:32 am

hotrock wrote:l'm new to this, so the main difference between the VLF and the Pi detectors such as the minelab SD's and GPX's is that they handle the ground minerialisation alot better so you don't get a whole lot of false signals like you would with a VLF detector. Those that have used both a VLF and PI detector how much better do you find the PI machine ? do you find alot more gold and is detecting alot more enjoyable because you are not digging on false signals anymore? what VLF detector handles minerialsiation the best? is there a VLF machine that handles the mnerialsation almost as good as a PI?



Gday Hotrock

Firstly vlf detectors were the ducks guts in detectors in their day, and thousand and thousands of ounces of gold were found with them, and vlf detectors do have a far superior descrimination ability than that of the pi detectors, so in some circumstances they are a more suitable machine to use, say for instance if you wanted to detect a seriously rubbishy site, say an old goldfields townsite, then you would want a vlf machine that would have the ability to handle the mineralised soil conditions and also be able to descriminate out most of the unwanted ferrous trash scattered about the place as well, one machine particularly good at this is the Minelab soveriegn gt, there are probably others as well that will do a good job.

Some vlf machines such as the Fisher gold bug, Minelab eureka gold, Whites tdi, Minelab xt series,etc were built with nugget hunting in mind so they will handle a lot of the variable soils found in the goldfields, better than your run of the mill cheapie coin detector will, but there are areas that they will not handle and their depth ability is seriously effected, they will also produce so much noise that even hearing a target will become impossible, basic coin machines will almost always react in the same way, they will squeal like a stuck pig with each swing.

Pulse induction detectors re opened the goldfields and this was due the their ability to handle highly mineralised ground, and had a substantial depth advantage over the vlf machines so once again many thousands of ounces of gold was being extracted from ground previously worked with vlf detectors and ground that was far too hot for the vlf machines to handle, pi machines have evolved over the years and now have the abilility to find really small nuggets where the very early models were excellent on outright depth but had poor sensitivity, this is the very reason that few large nuggets are found on worked ground, and far more smaller pieces are found.

You will still in some instances get spurious ground noises with a pi detector, often a seasoned detectorist will be able to descern a ground noise from a gold nugget response, but this is hit and miss on some ground so the general rule of thumb is to "dig everything" until are satisfied what it is, the common feeling on the descrimination of the pi detector would likely be that its not very accurate, as it will not work to full depth and will only work with dd coils, mostly its not used at all.

Detecting wih a pi machine is the way to go if you are serious about hunting gold nuggets, like I said there are some vlf detectors that will find nuggets, but if you want to find gold in most conditions on a more or less regular basis then you are far better operating a pi machine that built only for that purpose, one of the other things with pi detectors is that there is an astounding array of add on products from regulated battery systems, to signal enhancers/boosters, and not to mentioned almost any size and shape of coil that you can want for all types of terrain.

Anyway I hope this answers some of your questions.

cheers

stayyerAU







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Re: VLF vs PI detectors

Post  Aussiedetecting on Thu Jan 19, 2012 8:33 am

The first step to understanding the difference is to understand what they are.
VLF - Very Low Frequency detectors are great for coins & there are some fantastic gold machines as well. These detectors emmit either a single or multiple low frequency into the ground. To name a few Fisher Gold Bug Pro Dp, Fisher F75, Garrett AT Pro & AT Gold. A VLF detector can be swung reasonably quick and you cover a lot of ground quickly.
PI - Pulse Induction detectors emmit pulses into the ground and generally require the operator to work at a slower pace then the VLF detectors. As everyone knows the Minelab gold detectors utilise this tehnology very well. But the Garrett Infinium also utilises this technology and compared to the GPX series is a well priced detector.
I use the VLF machines, mainly the ones that I have mentioned, and have had some very good finds. I endeavor to get in the Infinium so that I can have that onboard to use & hire. Mainly out of curiosity for myself.
I'm sure the Minelab guys will post and give you a better idea on how they perform. Hope I've been able to help.
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Re: VLF vs PI detectors

Post  Guest on Thu Jan 19, 2012 10:04 am

A couple of very informative posts there.

My only add on is that the Infinium does discriminate the difference between gold and iron to the detection depth of the target and it does this with both Mono and DD coils. Like any discriminator it has its foibles and is not always accurate but the Infinium iron/gold discrimination is way better than what is found in any other PI metal detector.

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Re: VLF vs PI detectors

Post  slimpickens on Thu Jan 19, 2012 10:16 am

Hi Adrian, What depth do you think the infinium will find a one gram nugget in highly mineralised dirt? Just a rough guess will do. Question
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Re: VLF vs PI detectors

Post  Prospecting_Australia on Thu Jan 19, 2012 12:52 pm

The old visage of which is better, VLF or PI, pokes it's ugly face up yet again, and only a week after the last time!

There's no doubt that the Minelab GPX is the detector of choice for most prospectors. They simply are unsurpassed in performance and depth, particularly in moderately or heavily mineralised ground. But like most detectors thay have limitations. Unfortunately, Minelab and their proxies prefer to keep any limitations and disadvantages under wraps. Users therefore incorrectly assume their detector will find gold anywhere and everywhere, and under any conditions. This is incorrect - no one detector can be perfect under all conditions - that's simply impossible.

The secret is to find the limitations of the GPX and use this to your advantage. Each locality will have conditions that may or may not suit a GPX, in much the same way each locality demands specific settings and coils. For most people, however, this is not even a consideration - they simply turn on their GPX and go for it. They use the one detector for everything - old ground, new ground, scraped ground, thrashed ground, virgin ground. You name it and the one sublime, magical detector does it all! Changing coils and adjusting settings can only go so far to compensate for changes in ground conditions, but you can go one step better by first determining what type of detector would be most suitable under the prevailing conditions.

GPX detectors are not particularly useful for detecting fine specimen gold, or tiny shallow gold, or reefs and leaders. And the list goes on... Find it's limitations and you will find more gold at the end of each day.

Paul Zorich
Author Prospecting the Murchison
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Re: VLF vs PI detectors

Post  Nohave on Thu Jan 19, 2012 2:07 pm

I think stayyerAU has covered all points you asked.


Then allow me to disagree with you on

hotrock wrote: because you are not digging on false signals anymore?

From my experienced there are false signals while using PI . There will be false signals which created by patch of red dirts not so deep . It's ok for normal size coils though .

However I did find some false deep signals while using 25" coil and sounded like deep nugget.

Imagine ..digging wide and deep holes Embarassed Embarassed Embarassed Embarassed

Luckily I hired someone to do the digging but he was unhappy and laid down in his holes he hug.

Evil or Very Mad Evil or Very Mad Evil or Very Mad Evil or Very Mad Evil or Very Mad
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Re: VLF vs PI detectors

Post  Guest on Thu Jan 19, 2012 3:08 pm

shiraz wrote:Hi Adrian, What depth do you think the infinium will find a one gram nugget in highly mineralised dirt? Just a rough guess will do. Question

Too many variables to say with any certanty but as a very rough guestimate, anywhere from the surface to 6 inches in extreme ground (ground that will strongly attract a supper magnet)with the 10 x 14 mono.
In low iron high salt deeper for sure.
I figure on about 60% of what a GPX could do with a similar size coil in the same ground.
I am unsure of how well the MLs penetrate solid iron ore but can say that the Inf does a pretty fair job.
The MLs will without doubt, hit very small nuggs better (0.5 gm and smaller).
My Inf will find 0.14 gm bits with all of the avail coils but this seems to be a bit out of the ordinary for the Inf and most operators work on approx 0.5gm as a min size that any Inf user should be able to detect.

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Re: VLF vs PI detectors

Post  Guest on Fri Jan 20, 2012 7:57 am

Prospecting_Australia wrote:The old visage of which is better, VLF or PI, pokes it's ugly face up yet again, and only a week after the last time!

There's no doubt that the Minelab GPX is the detector of choice for most prospectors. They simply are unsurpassed in performance and depth, particularly in moderately or heavily mineralised ground. But like most detectors thay have limitations. Unfortunately, Minelab and their proxies prefer to keep any limitations and disadvantages under wraps. Users therefore incorrectly assume their detector will find gold anywhere and everywhere, and under any conditions. This is incorrect - no one detector can be perfect under all conditions - that's simply impossible.

The secret is to find the limitations of the GPX and use this to your advantage. Each locality will have conditions that may or may not suit a GPX, in much the same way each locality demands specific settings and coils. For most people, however, this is not even a consideration - they simply turn on their GPX and go for it. They use the one detector for everything - old ground, new ground, scraped ground, thrashed ground, virgin ground. You name it and the one sublime, magical detector does it all! Changing coils and adjusting settings can only go so far to compensate for changes in ground conditions, but you can go one step better by first determining what type of detector would be most suitable under the prevailing conditions.

GPX detectors are not particularly useful for detecting fine specimen gold, or tiny shallow gold, or reefs and leaders. And the list goes on... Find it's limitations and you will find more gold at the end of each day.

Paul Zorich
Author Prospecting the Murchison



Gday Paul

Both pi and vlf detectors still have their places as tools for locating gold, but reality is reality, I know many many prospectors both professional and hobby alike and do not know one person who uses anything other than a pi detector for their main detector, this is for the simple reason that they find the most gold with it simple as that.

Your statement

"GPX detectors are not particularly useful for detecting fine specimen gold, tiny or shallow gold, or reefs and leaders. And the list goes on... Find its limitations and you will find more gold at the end of each day".

This comment has me somewhat perplexed and I think is somewhat misleading, I can tell you from personal experience and from the finds I have seen made by others that a gpx detector is capable of all of these things, but remembering that the average detectorist spends most of their time just looking for nuggets,they will get a few here and there and then they move on, they dont spend the time and expend the effort in a lot of cases to try and locate a source, this is prospecting not detecting and there is a difference between the two.

cheers

stayyerAU




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Re: VLF vs PI detectors

Post  goldslugger on Fri Jan 20, 2012 10:30 am

stayyerAU wrote:
Prospecting_Australia wrote:The old visage of which is better, VLF or PI, pokes it's ugly face up yet again, and only a week after the last time!

There's no doubt that the Minelab GPX is the detector of choice for most prospectors. They simply are unsurpassed in performance and depth, particularly in moderately or heavily mineralised ground. But like most detectors thay have limitations. Unfortunately, Minelab and their proxies prefer to keep any limitations and disadvantages under wraps. Users therefore incorrectly assume their detector will find gold anywhere and everywhere, and under any conditions. This is incorrect - no one detector can be perfect under all conditions - that's simply impossible.

The secret is to find the limitations of the GPX and use this to your advantage. Each locality will have conditions that may or may not suit a GPX, in much the same way each locality demands specific settings and coils. For most people, however, this is not even a consideration - they simply turn on their GPX and go for it. They use the one detector for everything - old ground, new ground, scraped ground, thrashed ground, virgin ground. You name it and the one sublime, magical detector does it all! Changing coils and adjusting settings can only go so far to compensate for changes in ground conditions, but you can go one step better by first determining what type of detector would be most suitable under the prevailing conditions.

GPX detectors are not particularly useful for detecting fine specimen gold, or tiny shallow gold, or reefs and leaders. And the list goes on... Find it's limitations and you will find more gold at the end of each day.

Paul Zorich
Author Prospecting the Murchison



Gday Paul

Both pi and vlf detectors still have their places as tools for locating gold, but reality is reality, I know many many prospectors both professional and hobby alike and do not know one person who uses anything other than a pi detector for their main detector, this is for the simple reason that they find the most gold with it simple as that.

Your statement

"GPX detectors are not particularly useful for detecting fine specimen gold, tiny or shallow gold, or reefs and leaders. And the list goes on... Find its limitations and you will find more gold at the end of each day".

This comment has me somewhat perplexed and I think is somewhat misleading, I can tell you from personal experience and from the finds I have seen made by others that a gpx detector is capable of all of these things, but remembering that the average detectorist spends most of their time just looking for nuggets,they will get a few here and there and then they move on, they dont spend the time and expend the effort in a lot of cases to try and locate a source, this is prospecting not detecting and there is a difference between the two.

cheers stayyer
pirat too true S. TRUE PROSPECTING IS NOT DETECTING. Shocked you can, and will find GOLD without a detector! sure they are an adjunct in prospecting. who finds the most gold? prospectors, or detectors? also, some guys with gpx 5000,s find heaps, some don,t.? $6500 goes a long way towards prospecting. dunno. Cool
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Re: VLF vs PI detectors

Post  Prospecting_Australia on Fri Jan 20, 2012 4:54 pm

Ha! I've managed to perplex an old hand. Well it just goes that even an Old Dog can be taught new tricks.

Before going further, let me make it very clear that nowhere in my post did I imply a PI was not my main detector. It is, and has been since 1995. My post was to bring attention to the limitations of PI technology - a gap which modern VLFs can take advantage of in skilled hands.

GPX detectors are not particularly useful for detecting fine specimen gold, tiny or shallow gold, or reefs and leaders. And the list goes on... Find its limitations and
you will find more gold at the end of each day.
This comment has me somewhat perplexed and I think is somewhat misleading, I can tell you from personal experience and from the finds I have seen made by others that a GPX detector is capable of all of these things


This is incorrect. In 1995 the SD became my detector of choice but I kept my VLF because it still found gold the SD missed. Today I use a GPX 4500 and I still carry a VLF that still finds gold the GPX misses. When I'm on gold I want to make sure I am not leaving any behind, even if it means going over the same area a second time with a VLF. I do not wander aimlessly until I find a nugget or two and then move on. When and if I move away from gold I will need to be convinced that I am not leaving any behind. And let me stress again for the benefit of those who are not yet convinced - PIs can and do leave gold behind.

Example 1. Location: West Pilbara

Bulldozed and heavily dryblown area on the side of a hill. Exceptionally quiet ground well suited for high frequency VLF detectors. Over 60 kilograms of nuggets were reported to have come from the area using metal detectors. Has been well and truly flogged since. During our visit, my wife was using a Gold Bug 2 and I a GPX 4500. We both consider ourselves highly competent with the detector of choice.

Day 1: I head to lower ground using a 11" coil, hoping to score a bigger nugget or two that may have been missed, while my wife heads towards the upper slopes of the hill. I find one piece for the day weighing 0.3 gram while my wife picks up 13 pieces for a total of 4 grams. Average depth of her nuggets were 1-2" below the surface. Many of them were actually specimens or very small nuggets that produced no discernible signal to my GPX when I waved my coil over them. This was most likely gold that had been passed over by earlier PIs, and not just MISSED!

Day 2: I changed over to a 8" coil and attacked the upper slopes while my wife tried further downhill. My find was 9 pieces for a total 5.6 grams. Not a bad effort. The wife blames me for kicking her off the nugget hotspot, however, most were well and truly too deep for her detector. Her find was 2 pieces for 0.7 grams. Missed pieces probably.

Example 2. Location: West Pilbara

Several kilometres west of the area in Example 1, where heavy bulldozing was centred on an old dryblown creek. Uphill from the creek are quartz flats with several small quartz blows. Again very quiet ground, possibly even more so than Example 1. Once again my wife used a Gold Bug 2 and I a GPX 4500 with 8" coil. I spent half day on the quartz flats finding nothing before heading down into the creek. Found two small nuggets (weight unknown; possible 0.2-0.3 grams each). My wife concentrated on the quartz flats and immediately began picking up specimens and nuggets. Gold was very small, so she changed over to a small 7" elliptical coil. Her find for the day was 18 pieces for a total of 3.2 grams. Again, majority of her pieces were not detectable by the GPX, even with the 8" coil!

Example 3. Location Mount Regal Patch, Karratha

Despite the name, area consists of numerous patches, some exceptionally large, but well and truly flogged. Whole area is highly mineralised due to heavy ironstone concentration and well suited to PI detectors, however, one patch is relatively ironstone-free and quiet. I used an 8" coil with the GPX as I suspected the area produced mainly specimen gold. Found nothing but an old button while my wife was raking them in like there was no tomorrow. One after another, they just kept coming. For the first time in ages I felt a distinct disadvantage at using the GPX. Eventually the gold thinned out, so I asked her to try a spot where the bulldozers exposed a layer of gravel. I suspected most of the gold would have been trapped on this layer, long ago picked up, but perhaps some tiny pieces remained. On the very first wave of her coil she looked up at me and said "This place is full of rubbish, Paul."

"Show me." was my only reply.

So she pinpoints the most obvious signal, scoops up a handful and drops it onto the detector coil. She spends a couple of seconds brushing it around before looking up and saying "Its a nugget." I can't remember how many she picked up on the day but it was a lot, and it was impressive.

These are my observations based on recent experiences taken from dairies of our travels. Like you, I have been detecting for a very long time and I don't mind sharing my experiences with others. I simply would not even consider heading out prospecting without at least one good VLF detector with me.

I'm not sure what you're driving at in your last statement. Using a detector to locate gold is termed Electronic Gold Prospecting. Most people are out there swinging to find gold and would welcome any advice to help them improve the quantity of their finds, whether it be nuggets, specimen or reef. As users gain experience and become more confident they may wish to try new techniques and challenges. Not everyone will stay content with wandering aimlessly for a nugget or two! What they choose to call themselves, whether detectorist or prospector, seems like nitpicking to me.

Paul Zorich
Author Prospecting the Murchisom




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Re: VLF vs PI detectors

Post  Jonathan Porter on Fri Jan 20, 2012 5:49 pm

Prospecting_Australia wrote:The old visage of which is better, VLF or PI, pokes it's ugly face up yet again, and only a week after the last time!

There's no doubt that the Minelab GPX is the detector of choice for most prospectors. They simply are unsurpassed in performance and depth, particularly in moderately or heavily mineralised ground. But like most detectors thay have limitations. Unfortunately, Minelab and their proxies prefer to keep any limitations and disadvantages under wraps. Users therefore incorrectly assume their detector will find gold anywhere and everywhere, and under any conditions. This is incorrect - no one detector can be perfect under all conditions - that's simply impossible.

The secret is to find the limitations of the GPX and use this to your advantage. Each locality will have conditions that may or may not suit a GPX, in much the same way each locality demands specific settings and coils. For most people, however, this is not even a consideration - they simply turn on their GPX and go for it. They use the one detector for everything - old ground, new ground, scraped ground, thrashed ground, virgin ground. You name it and the one sublime, magical detector does it all! Changing coils and adjusting settings can only go so far to compensate for changes in ground conditions, but you can go one step better by first determining what type of detector would be most suitable under the prevailing conditions.

GPX detectors are not particularly useful for detecting fine specimen gold, or tiny shallow gold, or reefs and leaders. And the list goes on... Find it's limitations and you will find more gold at the end of each day.

Paul Zorich
Author Prospecting the Murchison

The Minelab and their proxies have been finding gold missed by the VLFs since 1995, if the gold is small or has a very fast time constant and the mineralisation is not too severe then yes get yourself something like the GBII or if there is a lot of trash about mixed with gold and its shallow then a good discriminating machine such as a Sovereign GT might fit the bill.

However in Australia with our particular brand of mineralisation there really is......
the one sublime, magical detector (that really) does it all!
Currently its the GPX 5000 and for good reason.

Heres a pic of 400 good reasons, found over a 12 day period last season north of Meekatharra.




......Minelab and their proxies prefer to keep any limitations and disadvantages under wraps.
I'm curious what is meant by this remark?

JP
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Re: VLF vs PI detectors

Post  Aussiedetecting on Fri Jan 20, 2012 6:05 pm

Ha told ya the Minelab guys would come out of the wood works. I like the "400 reasons" for a GPX 5000.
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Re: VLF vs PI detectors

Post  tricky 1 on Fri Jan 20, 2012 7:50 pm

aussiedetecting. we all know jp has been detecting since almost day 1 and has found more gold than the rest of us could dream of. could you please tell us " minelab lovers " how much experience you have and how much gold you have found with your detector so we can compare the true ability of each machine.
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Re: VLF vs PI detectors

Post  Aussiedetecting on Fri Jan 20, 2012 8:04 pm

Just to point out, I was having a joke.
I've got 10 years detecting experience under my belt, mainly coins & relics. Over the last couple of years I've come into the gold detecting game. I'm not saying that there's anything wrong with the Minelab detectors & the higher end models certainly do hold their own. Hey I even started out on a Minelab musketeer advantage, great to learn on & you really did have to learn it.
The Garretts, Fishers, Teknetics, Whites, Tesoros & Bounty Hunters are really the more affordable detectors that you don't have to shell out $6000 or $7000 for.
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Re: VLF vs PI detectors

Post  Guest on Sat Jan 21, 2012 8:07 am

Prospecting_Australia wrote:
GPX detectors are not particularly useful for detecting fine specimen gold, tiny or shallow gold, or reefs and leaders. And the list goes on... Find its limitations and
you will find more gold at the end of each day.
This comment has me somewhat perplexed and I think is somewhat misleading, I can tell you from personal experience and from the finds I have seen made by others that a GPX detector is capable of all of these things


This is incorrect. In 1995 the SD.......


Hi Paul, not sure how someones personal experiences could be concidered incorrect.
0.08gr, that's not even a tenth of a gr with a 5000 coupled with a 14" coil. That's pretty small in my books. Aslo seen some nice leaders some super fine specimen gold all won this year with both the 4500 and the 5000.

The GPX series will do all these and remarkably well.

Cheers,
Steve

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Re: VLF vs PI detectors

Post  Guest on Sat Jan 21, 2012 8:14 am

tricky 1 wrote:aussiedetecting. we all know jp has been detecting since almost day 1 and has found more gold than the rest of us could dream of. could you please tell us " minelab lovers " how much experience you have and how much gold you have found with your detector so we can compare the true ability of each machine.


Gday

I wont tell you it will make you cry Sad

cheers Laughing

stayyerAU

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Re: VLF vs PI detectors

Post  detectoraid on Sat Jan 21, 2012 1:51 pm

My VLF has been sitting more, since the 5000 came out.

Fitted with a small coil like the NF Sadie or 6" round Coiltek and running fine gold it really becomes a Gold Bug Killer. What it missis isn't worth the time and effort to recover with a VLF in 99% of the locations I prospect.

I don't know of any detector that has ability to go as deep and/or as small as the 5000. You can simply cover more ground. And in this game inches are miles



But I'll still keep my VLF's for nostalgia's sake Smile

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Re: VLF vs PI detectors

Post  Prospecting_Australia on Sat Jan 21, 2012 3:24 pm

Hi Paul, not sure how someones personal experiences could be concidered incorrect.
It was incorrect because I did not like the implication my statement was misleading. It was not! It was incorrect because his personal experiences were unsupported. It was also incorrect because his opinion contradicted my own comparative tests. I spent a great deal of time testing and gathering material on this very subject – many months – so if anyone has their opinions, then please, bring along some evidence to support the argument.

0.08gr, that's not even a tenth of a gr with a 5000 coupled with a 14" coil. That's pretty small in my books. Aslo seen some nice leaders some super fine specimen gold all won this year with both the 4500 and the 5000.

A good point you raise regarding what someone considers to be a pretty small nugget or a super fine specimen. I also might consider a 0.08 gram nugget as pretty small but certainly not tiny or even very small. Under 0.05 is what I might call a very small nugget and I believe is doable with a GPX 4500, depending on other factors such as depth, coil, settings, orientation of the nugget, shape of nugget, technique and even approach direction. Too many factors to consider really. Question is should someone bother with even smaller nuggets – the tiny ones? I think yes, if ground conditions allow. To me this is easy-to-get MISSED GOLD! Besides, when you go over an area again using a VLF you can end up with plenty of missed smaller nuggets as well as the tiny ones. I guess not everyone will bother though. It's horses for courses, I guess. On an unrelated point you mentioned using a 14” coil. Nugget Finder I presume, and this beauty is one of my favourites as well.

Regarding super-fine specimens, I don't think we are in agreement there. To me a super-fine specimen would only have a few tiny specks of gold (or less) and most certainly not detectable by a GPX 4500, and I highly doubt even a GPX 5000, and even if the specimen was placed on top of the ground gold-side-up and a 8” coil used. On the other hand, fine specimens may very well produce a signal but if they were to be positioned gold-side-down then they can be missed. It is gold specimens in this class that the Gold Bug 2 excels, provided of course ground conditions allow.

If someone is lucky enough to find a leader with a GPX then most likely they walked over the top of it, or perhaps, the leader had shed some coarser specimens. Unfortunately I've never had this luck and always had to work extra hard for my leaders using a Gold Bug 2 to loam super-fine specimens back to the source. To be honest, I would have to say the Gold Bug 2 has found a great deal of gold for me, but if you took into consideration only the missed gold then this would probably only amount to 7-10% of my total finds, but it all adds up in my book.

The GPX series will do all these and remarkably well.

Again we are in disagreement here. My findings suggest otherwise.


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Re: VLF vs PI detectors

Post  deutran on Sat Jan 21, 2012 3:43 pm

A friend recently lent me one of those coiltek small ellipticals to try out on the 5000 in fine gold I think its 10 x 5 or something.I was getting tiny lead shot down 4-5 inches in cracks and crevices.(+3 small nuggets).
Its not a coil that would be in my kit as the 8" is more than adequate but the performance was just astonishing being able to find such small targets at depth.
I would say that with this setup gold could be found even in the most worked out ground.Your probably not going to get rich quick but you can get gold everyday and those little bits do add up.
I recently had a good find using the 17"x11"NFA it was 12 specimens from 1 hole beginning with a faint signal.5 were part of 1 rock and once broken open revealed some fine gold specks through the veins.These were not detectable and require crushing and panning off and I didn,t have a chance to try a small coil on them.
I have never tried a gold bug or similar but it would be interesting to go over some of these areas for a comparison.
Steve

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Re: VLF vs PI detectors

Post  Guest on Sat Jan 21, 2012 5:39 pm

Actually Paul,
0.04 with either 11" or 14" I can't say positively with which coil now, but it was witnessed.
May I suggest that just because you haven't seen something or because you haven't walked over something doesn't mean that's the same for everyone.

cheers,

Steve

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Re: VLF vs PI detectors

Post  kon61 on Sat Jan 21, 2012 7:08 pm


G'day Guys. My two cents worth.

I have used many a coil/detector combination in the past,until I witnessed what an 8x6 Sadie coil could do on a finely tuned GPX 4500 or 5000 on a 0.1 of a gram bit of gold,at what I would consider today as phenomenal,unheard of depth on fly s**t.I can confidently say that not even the high VLF frequency of the Fisher Gold Bug 2 will match it,regardless of the type of gold it is or whether the ground being hot or under milder mineralized ground conditions. Now this don't mean that I'm a Minelab fanatic who refuses to accept any other avenues other than Minelab pulse induction detectors,but Mine lab pulse detectors such as that we currently have in the GPX series,are the best small/large gold detecting equipment available on the market today.They aren't the most ergonomically designed or comfortable or lightweight detectors on the market either,but since no other company has seriously challenged them so far as to their gold detecting capabilities over a wide range of ground handling conditions,Minelabs gunna keep on excelling & laughing,all the way to the bank.

Cheers kon61.

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Re: VLF vs PI detectors

Post  GREENnuggetCONVERT on Sun Jan 22, 2012 1:57 am

@detectoraid.....wrote " But I'll still keep my VLF's for nostalgia's sake "
.................................................................................................
It may come in handy to get some coin for a bus fare one day.............
cheers......Trev....
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Re: VLF vs PI detectors

Post  detectoraid on Sun Jan 22, 2012 5:34 am

LOL,
I bought a bus with coins found……… with a coin detector back in the late 70's. At the time most of the parking meters in Phoenix were on a grassy strip and were constant producers. The one summer that I kept records, my parking meter finds totaled $1254.00 not a bad summer for a student.
I still love to coin and relic hunt in the ghost towns and mining camps, in fact recently I hosted American Digger magazine's on the road editor on a relic hunt along the Emigrant Trail (49ers gold rush) which passes through Northern Nevada and a hunt along the Carson River where the Comstock load silver was milled.




I found this 2.5 peso near a ranch (station) bunk house In AZ a few years back.

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Re: VLF vs PI detectors

Post  GREENnuggetCONVERT on Sun Jan 22, 2012 6:59 am

@detectoraid.....said...."I bought a bus with coins found"...can't beat that ( awesome )... lol!
well done good find,if Australia was as diverse and as expansive as the U.S. i would probably get into the coin side of things.
have watched a lot of coin and relic vids from the U.S. and Europe and it seems pretty full on as to what relics and coins are available
to be found.i know there is a fair amount of it that goes on over here but nothing comparing to all of you....i actually like all the old war relics
that are found over there,have seen some great old firearms etc recovered by detectorists....
again well done.
cheers....................Trev....
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Re: VLF vs PI detectors

Post  Prospecting_Australia on Sun Jan 22, 2012 6:14 pm

May I suggest that just because you haven't seen something or because you haven't walked over something doesn't mean that's the same for everyone.
Steve, you must be joking! Shouldn't I be the one asking this very question? Wink
Actually Paul,
0.04 with either 11" or 14" I can't say positively with which coil now, but it was witnessed.
I don't doubt for a single moment that a 0.04 gram nugget can be found with a modern GPX. Finding gold this size can be challenging and needs a whole new set of skills, particularly if you are pulling them up regularly. A few may even take it to the next level and find smaller still. Laughing


An ounce of littlies found north of Meeka last year with a GPX 4500 using 11" coil mostly to cover ground faster. A couple of spots also used 8". Spent one week there, but unfortnately 3-4 days wasted due to bad EMI. Most of the nuggets are under 0.3 grams, the largest 0.7g

Some of the sub 0.05 grammers from above. The small one on the upper right is smaller still and found using the 11". The tiny one on the left is a fragment from a specimen accidently chipped when digging it out and then detected again by my showy wife using a GB2. Haven't done an SG test yet affraid I've got really small fingers so I included a 0.1 grammer 2nd left as a guide.

---------------------------------

My point isn't about the size of gold someone can find with their GPX, but how much gold it can leave behind. Finding the occasional very small nugget means nothing. When gold of this size is present there is a very good chance something will be left behind. The only way to be 100% sure is to go over it again, preferably with a VLF, assuming of course the ground is suitable. So have you tried this Steve? Has anyone you know tried this? If not, then how can you possibly be sure a GPX hasn't left anything behind?

So, may I suggest that just because you haven't seen something or because you haven't tried something, doesn't mean it's the same for everyone.

Don't get me wrong. There is nothing wrong with using the one detector, especially if you are on a budget, a hobbyist, or just out on a day's detecting. But if you are serious about finding gold then you would most likely carry more than one detector, just as you would carry more than one coil. The secret is to select the right tool for the right job and that does not always have to be a GPX.


Old dryblowing heaps are well suited to VLFs, particularly in quiet ground. My wife putting another micro-nugget into her collection jar.


Specimen and nugget collection found with a Gold Bug 2. The six pieces on the right were found with a GPX 4500 as a follow-up for deeper gold. Total weight is about ounce & half of gold.


Specimens found with a Gold Bug 2 in one of the most flogged places imaginable. The two largest pieces on top left were found on scrapes and probably walked over a hundred times. The gold might look a lot but it is rice-paper thin on surface only, and was for all practical purposes undetectable by a GPX. This was confirmed by a third person.


A two-and-half-ounce sunbaker. Found using a GPX 4500 but easily detectable with any VLF. My wife insists it had her name on it because it was on top, even though she never walked within 5 kms of it.


Last edited by Prospecting_Australia on Mon Jan 23, 2012 12:12 am; edited 4 times in total
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Re: VLF vs PI detectors

Post  Kon61gold on Sun Jan 22, 2012 9:51 pm

tricky 1 Today at 19:30


i annoyed the daylights out of a friend of mine who has been detecting for 30 years when i was thinking of starting detecting again, and he gave me the best advice. if you want to find gold, buy the latest minelab, if you like walking around the bush, buy something else.all the detecting areas have been worked for years with vlf and the early pi machines and to have the best chance you need the best gear. the 4500 payed for the 5000 and the vlf which gets used in high trash areas to discriminate the gold from the rubbish and saves a lot of digging. the vlf is also good at keeping my son occupied but is a real handfull in highly mineralised ground. i only had 3k to start and borrowed the rest to buy the 4500 and was prepared to pay it off the card at about 200 a month but was able to pay it off over 6 months with the gold it found. walking around the bush is a lot of fun but is a lot better when it pays its own way.

tricky 1




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Re: VLF vs PI detectors

Post  Guest on Sun Jan 22, 2012 10:53 pm

Sorry Paul, there must be some missunderstanding here or I'm just plain flat out missing something.

I am refering to your comment "GPX detectors are not particularly useful for detecting fine specimen gold, tiny or shallow gold, or reefs and leaders"

All I am saying is I dissagree.
Why am I saying that? Because I've done it, and I've also seen other people do it. with both GPX4500's and GPX5000's

Now again I might be missing something, because the way I read the rest of your pile of words is that it can't be done because we have no evidence.
And the way I read that is you don't believe it because we didn't provide photos or videos? For that I appologize, will a stat dec from my mum be okay?

Cheers,

Steve

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Re: VLF vs PI detectors

Post  Jonathan Porter on Mon Jan 23, 2012 8:04 am

Paul is 100% correct on what he's saying about gold being missed by the PIs, but is 'being missed' the correct term. Theoretically the gold we're now finding is also missed gold so its kind of a mute point. However a lot of people coming from the VLF era are well aware of the types of gold that was originally being found regularly with the VLFs and also more importantly the types of ground frequented for detecting purposes due to the limitations of the tech.

An example, Frieda and I spent 4 weeks in Nullagine in the winter of 1994, mostly in and around the local haunts such as The Dromedaries, The Razor Back, 5 mile etc, all we did was hit the scrapes scrounging out tiny little nuggets to the tune of 30 or more a day each, from memory the biggest nugget of the duration weighed in at a paltry 1.3 grams, yet we averaged nearly 2 ounces a week for 800 plus nuggets, thats good going even by todays standards.

Guess what? All that type of gold is still laying there waiting for people to re-enthuse themselves to bother going after it, seems like Paul and his wife are making the effort. The GPX 5000 is capable of finding some of that gold if you set the detector up correctly but a lot of it will stay in the ground for obvious reasons (in Nullagine the nuggets tended to be roughish in nature having not shed far from the source so not good for PIs). However I would still love to go back to some of our old haunts and 'VLF my 5000' to see what we missed.

For a VLF to be productive there are two things required, it needs to be a gold field with low mineralisation that has produced large amounts of fine dry blow like gold, some good examples of this are places like Nullagine, certain areas on the Palmer River, Halls Creek, Tiboorburra, Pipe Clay patches in the Golden triangle etc or the nuggets have to be big enough to stand out from the mineralisation (hard to find these places now days due to PI technology).

From my standpoint its not a case of turning up my nose at the gold a VLF can get but instead maximizing my time during the winter months chasing the weights, which means either targeting areas where the mineralisation is high or spending my time in new country looking for a patch or two. In both cases the PI machines win the discussion hands down due to two major factors, namely ability to ignore the mineralisation and find tiny nuggets but also and probably more importantly when you take the first reason into account, the ability to cover vast expanses of ground in a small amount of time whilst maintaining sensitivity.

Generally speaking the larger gold with be in the deeper sections or more problematic areas, which means if you're spending your time sniffing out tiddlers with a VLF you're not spending your time in the deeper sections chasing the heavier gold. Paul seems to have a good thing going, with his better half chasing the smaller gold when it suits while he invests his time in looking for payday gold.

......Minelab and their proxies prefer to keep any limitations and disadvantages under wraps.

Would still like an explanation to this comment though?

JP
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Re: VLF vs PI detectors

Post  Guest on Mon Jan 23, 2012 8:35 am

Gday

GPX detectors are not particularly useful for detecting fine specimen gold, or tiny shallow gold, or reefs and leaders. And the list goes on... Find it's limitations and you will find more gold at the end of each day.

I still believe this statement to be misleading because like so many others who have commented, I have myself proven otherwise to what it implies, I am not arguing that a pi detector will outperform a vlf detector in all situations but I will argue that a pi detector will outperform a vlf detector for a higher percentage of the time, and if you were to only be able to carry one detector with you then a pi detector would be the way to go.

Just because I did not back up what I said with facts and figures, that can be collated to say anything you want them to say, I does not mean that I have not experienced otherwise myself or seen others in the field do things contrary to what has been suggested, If I had not experienced otherwise I would not have made a comment in the first place.


cheers

stayyerAU







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