Your Pulse Induction Is Worthless On Large Gold

[mn90403]

Steve Wandt jewelry is highly prized as he used great care in making such jewelry.  There are other Sierra jewelers that survive him.  We should make a thread for them.

[s.young]

I found this at 10'' a few years ago with a GPX 4500 & 14 coiltek elite & was a loud as I thought trash or bullet.

[GotAU?]

4 minutes ago, s.young said:

I found this at 10'' a few years ago with a GPX 4500 & 14 coiltek elite & was a loud as I thought trash or bullet.

Nice! Hope you went back to that spot with a VLF!

[EL NINO77]

12 hours ago, Gold Junkie said:

If it looks like this.... 

I have found my share of this type of gold this past season, and it truly is invisible to the axiom.  Now before the  6000 boys start talking smack, it also could not see a piece of this type of gold. The larger piece picture in my fingers is about 49 grams. As you can see it is full on all sides. The smaller piece is about 14 grams. They are both pretty solid pieces, but the PI'S just don't hear them unless they are pretty much touching the coil. These were found with the Manticore.  The larger one banged hard at 8+ inches deep.  To my amateur ear, they sound just like a piece of wadded up foil. This type of gold rings up as a very strong 02 on the Manticore.  My theory was this gold must be flour type gold compressed into the quarts pocket, opposed to being molten when formed. I proved that theory to myself when I was poking and prodding on a piece, and some broke off into flour type gold. I just wanted to post this to show how important having a vlf is in this game. It's not only for cleaning up the tiny bits. In my case the vlf was my only option to find the larger pieces. 

I hope this helps someone find some big ones they never knew were there!

You said.. that for a larger piece at a depth of 8" the Manticore gave VDI 2...
Most detectorists take the VDI number on the detector as a numerical identification of the target... I don't..
In fact, the VDI number of the target on the VLF Detector /and especially the multifrequency one/ provides you with additional information, namely how conductive the given target is..regardless of its size...
The fact that the given relatively large and heavy gold stone gives VDI 02 on the Manticore...says that this target is an extremely very low conductive target..-which means that it can be very poorly detectable, even undetectable for PI detectors...but high-frequency VLF detectors can detect it...
It is definitely a good lesson for the future...it is good to combine gold detection with both PI and VLF detectors..
In any case, I congratulate you on such a result... and I wish you further successes in detection.. now that the price of gold is really high... the value of such a success is tripled..

[abenson]

I found these 2 nuggets with Axiom running fine. The big one was a foot deep the small one 6 inches. So I wouldn't say you're goung to miss it all with a PI.

[Caliche]

I'm super new to prospecting, but have found a fair amount of gold jewelry in dry sand, which means minimal background mineralization interference and a clean signal.  I think about VDI as a formula, something like this:

Size x (Multiplier for Given Metal)= VDI

So on modern Minelab VLF's with 0-99 scale, a tiny solid bit of low conductor (gold) is 0-2, but 10g of solid 18k gold is ~60. 

A 0.3g bit of solid medium-high conductor (aluminum square tab) could be 32, but a big solid chunk (melted beer can blob) could be 70.  A weightless bit of aluminum foil is 0-4.

A tiny bit of solid high conductor (silver earring) could be 60, but a big solid chunk (half dollar) is 94.  

So if VDI is below 60, it's a low or medium conductor, and VDI varies with size x material.

If VDI is above 60, it's a medium or high conductor and VDI varies with size x material.

So if you get a 0-2 on a Manticore, it's definitely a small  bit of metal, regardless of conductivity, and regardless of how many small bits there are in that one spot.  Could be 50g of gold bits, but the VDI will only reflect the largest bit in the cluster.  So to say that a PI won't pick up large gold isn't quite accurate, as it certainly will.

[Gold Junkie]

1 hour ago, abenson said:

I found these 2 nuggets with Axiom running fine. The big one was a foot deep the small one 6 inches. So I wouldn't say you're goung to miss it all with a PI.

My point was, there is larger gold that the PI doesn't get. It is a rare case Im sure, but it's out there.

[Jeff McClendon]

41 minutes ago, Gold Junkie said:

My point was, there is larger gold that the PI doesn't get. It is a rare case Im sure, but it's out there.

Your point is a very good one but it would be even more clear if you included the words “some specimen” larger gold. It would also help any confusion if specimen was in your title.

 

[phrunt]

Well, it's a typical click bait title method 🙂

Gerry does classes on this stuff.

I've seen it myself even with small gold, some nuggets a detector should easily hit by size are missed entirely or need to touch the coil, VLF's never get the problem.   It's very common on the GPX 5000, and GPZ even gets the problem, as does the 6000, some nuggets they are just very weak on, I've not tried the Algoforce or Axiom on these tough little bits, they're long lost in my collection however the Algoforce is the only PI I know of that hits a number 9 lead pellet so it has the sensitivity to do well on these tough bits.  I haven't checked the GPX 6000 or Axiom on a #9 pellet I don't think, I must do that.  

It would be interesting to see if the Algoforce hits on that piece Gold Junkie found.