Nexus Coil Design

[Max]

copper nodules

Hi,
seems I've found an example of their existence entrusted by USGS.

Seems that is a quite rare (big) mix of copper nodules coming from a Colorado mine.

Also seems that USGS analyzed them in 1978 and found that are rare native copper specimens.

This prove nothing about halo effect, of course, but that these copper nodules exist for real even stand-alone and not only as inclusions of e.g. manganese or other things nodules.

Kind regards,
Max

[Nihil Roma Maius]

But you have also consider that there would be many of these micro-nodules not just one... a kind of "cloud" around the target in the few cms around it.

Seems an LRL argumentation ! But I think that this a better explaination of the phenomenon.

Kind regards,
Max

Ehhh!!! Of course, and this is the reason why electronic LRL acts good with old targets. I found a couple of 34 copper coins –25 mm diam each– and comprobe how the surrounding earth was affected by copper migration... like electrochemistry, galvanization of the soil! This enlarge the size of the object/s. Maybe is not viewable in an only coin, but yes with 34 corroded copper coins...

Non ferrous causes more halo than ferrous. In aparience ferrous causes more because targets iron in general are more bigs.

[Qiaozhi]

This is from an interesting link that was posted by sisco in the Tech Forum:

WHAT IS HALO EFFECT?
Halo effect makes targets that have been in the ground a long time appear much larger than they actually are. Imagine an iron nail that has been in the ground for a number of years. As moisture in the ground slowly rusts the nail, forming iron oxides and iron salts, these oxides and salts migrate from the surface and tend to form a “halo“ around the nail. This, of course, makes it a lot “easier“ for a metal detector to detect. This effect is basically the same for most metals. When the target is dug, this halo effect (which takes years to form) is destroyed. So if you find a target due to the halo effect, and, for instance, it was a very weak signal, you will find that if you rebury it at the same depth, you will probably not now detect it (unless you leave it for five years!). For you beach-hunters, halo effect rarely has time to build up and will be destroyed if the ground moves. Relics are often found at greater depths due to these effects.
Gold can be very hard to find due to the odd shapes that are often formed. Halo effect really helps us liberate a lot of gold, as most gold hasn’t moved in a long time! But gold doesn’t rust or corrode I hear you say. Correct. Often where you find gold there are also salts and chemicals (like cyanide) and these will leach out the gold into the surrounding minerals, causing a halo effect.

The originator is: Ralph @ Sun Ray Detector

[J_Player]

Hahahahahahaaa... I never saw a long-time buried coin that looked like that!

I once did an experiment, where I took a solid copper alloy USA penny and filed it into tiny granules of copper powder. I then poured epoxy over the powder to make a new epoxy coin that contained all the copper from the penny. When it dried, I ran some air tests to compare the epoxy powder penny with a real penny. The result was I could barely get a faint signal from the epoxy penny when I touched it against the most sensitive part of coil, but I got a regular signal from the real penny.

Both coins contained the same amount of metal, only one had the metal in the form of tiny granules. Now what would happen when we make those metal granules tiny enough to be considered a colloid? Would they become completely invisible to any metal detector?

It seems to me a metal detector depends on generating eddy currents to detect metal. This requires a sizable mass of metal for a current to form a loop in the surface. Tiny granules have very little ability to generate measurable eddy currents, even collectively when compared to an equal amount of a single solid piece of metal. Also, I have never seen any testing that shows any dissolved salts of copper or other non-ferrous coin metals in the soil respond to any conventional metal detector. My understanding is dissolved metal salts are not conductive enough to generate measurable eddy currents.

The testing for ferrous halo showed that a substantial part of the ferrous metal target was left behind in the soil, having partially oxidized and exfoliated from the original specimen that was recovered. Many of the rusted fragments of the target that remained in the soil could still be sensed when held near the coil, much as a hot rock can be sensed.

But in the case of non-ferrous ancient coins, I have never seen any test showing a fragment of oxidation from the coin or a soil sample that gave any reading at all on a metal detector no matter how close it was held.

I often find corroded coins in the damp soil and the sand near the local ocean beaches where these coins are constantly exposed to wet salt. Some of the coins are embedded in a hard cementatious layer of sand and metal salt globule that can be several times the size of the coin. After breaking off this layer of metal salts and sand, I find this crust gives no reading on the metal detector. This includes the black crust material I find on silver coins as well as the green and white salts I find adhered to copper alloy coins.

My opinion is there probably is a halo effect on some long-time buried non-ferrous targets, but nobody has discovered exactly the reason why they experience this halo. I doubt anybody will have a provable theory about why they see the non-ferrous halo effect until they do some very precisely controlled tests to prove their theory.

See below for some USA coins found near the ocean:

[Qiaozhi]

My opinion is there probably is a halo effect on some long-time buried non-ferrous targets, but nobody has discovered exactly the reason why they experience this halo. I doubt anybody will have a provable theory about why they see the non-ferrous halo effect until they do some very precisely controlled tests to prove their theory.

I agree.

[Max]

Hahahahahahaaa... I never saw a long-time buried coin that looked like that!

I once did an experiment, where I took a solid copper alloy USA penny and filed it into tiny granules of copper powder. I then poured epoxy over the powder to make a new epoxy coin that contained all the copper from the penny. When it dried, I ran some air tests to compare the epoxy powder penny with a real penny. The result was I could barely get a faint signal from the epoxy penny when I touched it against the most sensitive part of coil, but I got a regular signal from the real penny.

Both coins contained the same amount of metal, only one had the metal in the form of tiny granules. Now what would happen when we make those metal granules tiny enough to be considered a colloid? Would they become completely invisible to any metal detector?

It seems to me a metal detector depends on generating eddy currents to detect metal. This requires a sizable mass of metal for a current to form a loop in the surface. Tiny granules have very little ability to generate measurable eddy currents, even collectively when compared to an equal amount of a single solid piece of metal. Also, I have never seen any testing that shows any dissolved salts of copper or other non-ferrous coin metals in the soil respond to any conventional metal detector. My understanding is dissolved metal salts are not conductive enough to generate measurable eddy currents.

The testing for ferrous halo showed that a substantial part of the ferrous metal target was left behind in the soil, having partially oxidized and exfoliated from the original specimen that was recovered. Many of the rusted fragments of the target that remained in the soil could still be sensed when held near the coil, much as a hot rock can be sensed.

But in the case of non-ferrous ancient coins, I have never seen any test showing a fragment of oxidation from the coin or a soil sample that gave any reading at all on a metal detector no matter how close it was held.

I often find corroded coins in the damp soil and the sand near the local ocean beaches where these coins are constantly exposed to wet salt. Some of the coins are embedded in a hard cementatious layer of sand and metal salt globule that can be several times the size of the coin. After breaking off this layer of metal salts and sand, I find this crust gives no reading on the metal detector. This includes the black crust material I find on silver coins as well as the green and white salts I find adhered to copper alloy coins.

My opinion is there probably is a halo effect on some long-time buried non-ferrous targets, but nobody has discovered exactly the reason why they experience this halo. I doubt anybody will have a provable theory about why they see the non-ferrous halo effect until they do some very precisely controlled tests to prove their theory.

See below for some USA coins found near the ocean:

Hi,
ocean's coins have no meaning about halo. The crust you can recover from them is probably made of oxides and salts, gives nothing useful about halo understanding or theories.

My idea is different. My theory is that, is the compact soil around the coin that contain the recollapsed metal in very small "nodules".
The more the time... the more their size and maybe number.

"It seems to me a metal detector depends on generating eddy currents to detect metal. This requires a sizable mass of metal for a current to form a loop in the surface. Tiny granules have very little ability to generate measurable eddy currents, even collectively when compared to an equal amount of a single solid piece of metal."

Sure, no big eddy currents there ! No big pieces of course.
But also a piece e.g. of very thin foil you can detect with a good and sensitive VLF.

I think that the effect is similar for very long time buried e.g. copper (>1000years) even if you cannot see if there is any copper nodule there using the eyes.

If you can detect a small piece of foil of few microns thickness, at few cms in the ground, why not some thousand 10um copper nodules around a coin can't give you a few cms boost ?

Fact is that when you break the soil sorrounding the matrix you probably destroy and make undetectable by MD just the halo.

During an excavation I've found some years ago a copper "patina-like" maybe of something 0.1 mm thickness at origin, 3x2cm, thinner than paper and I've detected with MD as a weak signal. It was just at 2cm under the center of the coil... and removing that stuff it broken in pieces like glass and then I cannot detecting anymore nothing. Object was of about 2600-2700 years old and cannot say more about.

I detected it by just some halo I think... cause haven't recovered metal just powder at the end, all green, so oxides.

For me remains a big mistery how it works, don't know if my theory is right or not, but I'm sure that phenomenon exist.

Kind regards,
Max

[J_Player]

Hi Max,

Fact is that when you break the soil sorrounding the matrix you probably destroy and make undetectable by MD just the halo.

Is this a fact or a theory? Perhaps you can demonstrate this "fact" to prove what most of us think is only a theory?

My idea is different. My theory is that, is the compact soil around the coin that contain the recollapsed metal in very small "nodules".

My actual test showed that when I took enough copper alloy filings to make up a complete coin, they were not detectable. In order for a metal object to be easily detected with a metal detector, eddy currents need a larger path to circulate in than are found in tiny filing grains. This leads me to believe even smaller microscopic "nodules" of metal would also be undetectable. Do you have any testing to show you actually detected these alleged nodules near a buried coin?

Best wishes,
J_P

[Max]

Hi Max,

Is this a fact or a theory? Perhaps you can demonstrate this "fact" to prove what most of us think is only a theory?

My actual test showed that when I took enough copper alloy filings to make up a complete coin, they were not detectable. In order for a metal object to be easily detected with a metal detector, eddy currents need a larger path to circulate in than are found in tiny filing grains. This leads me to believe even smaller microscopic "nodules" of metal would also be undetectable. Do you have any testing to show you actually detected these alleged nodules near a buried coin?

Best wishes,
J_P

Hi JP,
I wrote:

"
Fact is that when you break the soil sorrounding the matrix you probably destroy and make undetectable by MD just the halo.
"

the "probably" means I'm not sure of that: it's a theory not a fact.

I have no test that can give any proof about HALO generation.

It's just a idea. But halo effect is real.

Kind regards,
Max

[J_Player]

Hi Max,

I believe the halo effect is real also because I hear the same story from so many people all over the world. Some day maybe someone will make some real tests to show why we see this halo that nobody has certain knowledge of the principle.

Best wishes,
J_P

[J_Player]

User report for the NEXUS detector

I read a forum post from somebody who tried a NEXUS at Palm Beach, Florida. This is a beach hunter who regularly finds rings and other jewelry at the beach dry sand and submerged with his excalibur and Aquasound. This is not a scientific report, just a forum post of this hunter's impression of the Nexus.

Here is part of what he said:
...I try different settings and again I was amaze. Very deep working machine.
Read his post here: http://www.thetreasuredepot.com/cgi-...pl?read=108774

Looks like the submersible model Nexus works pretty good!

Best wishes,
J_P

[Woody.au]

The halo effect is not real, if anything it will reduce the magnetic field via their resistive component when they are now sulphide or oxide of the original metal. Suphides and Oxides are not detectable with a metal detector in small quantity. Its all in the the mind, we think of a halo as something that extends the diameter of the original object, like some Biblical artwork. Any dissolved material will have a bulk resistive component and make the return field much weaker.

[Max]

The halo effect is not real, if anything it will reduce the magnetic field via their resistive component when they are now sulphide or oxide of the original metal. Suphides and Oxides are not detectable with a metal detector in small quantity. Its all in the the mind, we think of a halo as something that extends the diameter of the original object, like some Biblical artwork. Any dissolved material will have a bulk resistive component and make the return field much weaker.

Hi,
you think so. That's ok for me if you think it doesn't exist for real.
Many people think the same as you.

Me too was thinking the same... that was a BS, before I saw it.
Think that the only way you could belive that is actually see it in action.

Problem is that in Australia you cannot. There aren't ancient items... I don't mean few years buried you could find in any place... but really ancient stuff , >1000years buried in the same undisturbed ground.

Almost impossible to find that stuff there.

I never saw any effect of this kind on e.g. few years old buried anything.
Cause of that, I think that when a manifacturer say that after few time the halo develops for non-iron targets it's just advertising.

Kind regards,
Max

[ivconic]

Hello halo!

I dont know who adopted term "halo" for the first time? But i refuse to name it "halo"....Phenomena is existing for real. I experienced it many times. Of course i dont have clue what is all about and cant explain it, but it is real for sure. All your remarks are true and i agree with those...but...no expalnations yet!?
Science, formulas,calculations...all disprove this, i know, but it is real and existing...!?
Regards!

BTW do not mix me with some of "beleivers" cose this subject is closely related to some wild explanations and theories from Remote Sensing threads....It should have nothing with those for sure, and i am not that man!

[Max]

I dont know who adopted term "halo" for the first time? But i refuse to name it "halo"....Phenomena is existing for real. I experienced it many times. Of course i dont have clue what is all about and cant explain it, but it is real for sure. All your remarks are true and i agree with those...but...no expalnations yet!?
Science, formulas,calculations...all disprove this, i know, but it is real and existing...!?
Regards!

BTW do not mix me with some of "beleivers" cose this subject is closely related to some wild explanations and theories from Remote Sensing threads....It should have nothing with those for sure, and i am not that man!

Hi ivconic,
it seems exist and no scientific proven theory about!
I know you are not LRLs addicted.
I think the same of LRLs: they don't work, can't work.

I know that many people use that argumentation for wild theories about LRL.
I don't... I know that the effect gives just a few depth more, few cms, using a sensitive MD, but you can notice that, you dug the object and then realize that it was at more than your detector maximum range !
Then in air you cannot detect it at same distance !

Why happens ?
I don't know! Just have some ideas/theory and no proofs of anything.

Best regards,
Max

[Woody.au]

If this "Halo" effect is real then the only possible scenario is that its increasing the ground noise around the target and that is adding to the signal. Then again it depends on the type of ground and the metal involved.

Maybe with ground water and conductive salts in the soil react with the target and make "ionic" conduction channels. In Australia I find that when a target partially dissolves into the soil the detection gets much weaker, but that is on items maybe 100 years old. When items have been buried for 1000 years then maybe some other explanation needs to be researched.