gold frequencies and trash

[Rick(ND)]

The more you dig the more your gold finds will be.
With the Tesoro and some others there is just the audio and no VID so you are digging most everything so you will find more trash, but also find gold and other interesting finds.
I started back in 1973 when there were really no disc. and detected a old park that had a lot of rusty bottle caps, but learned to tell the difference than a coin. I got most of my gold jewelry with it as I dug most everything . Now we have pulltabs we didnt have much of back in the 70s, so it is tougher now, but to know your detector well will help tell the difference.


Rick

 

[Southwind]

This is where I just don't understand a lot of detector manufactures thinking. A high frequency does make finding gold better, but to help finding gold in a high trash area takes a high resolution VDI. That is to say a detector with a lot of target segments in the lower -20 to +30 range. But from what I see manufacturers are lowering the number of target ID segments. One of the best detectors, at least in my experience, for telling the difference between trash and gold is the DFX with 191 target segments.

A good example is I have a 14k 12.2 gram Foxtail necklace I use for testing. All my lower resolution detector read it just like a piece of iron. On my DFX it read as a solid 0 to 2 where all iron reads in the minus range. Also having a high resolution/target segment count allows you to compare iron, which reads all over the place, to gold, which reads in a very tight VDI range only varying a few numbers and increase your odds quite a bit.

High frequency is key to detecting the gold, but high target ID segment/resolution is key to telling trash from gold.

Southwind --

While I will grant that there is SOME truth in your statement (but only some) that gold will generally read in a "tighter" range than iron, that to me seems like somewhat of a strawman. USUALLY, the issue isn't "is it gold, or is it iron" (though for some very small pieces of gold, or some bracelets, chains, etc. that might be the case), MORE OFTEN THAN NOT, the issue is "is it gold, or is it foil," or "is it gold, or is it a beaver tail," or "is it gold, or is it a ring tab," etc. etc. And those types of junk targets often DO have a tight VDI range...so the higher-resolution machine doesn't help you much, there.

Also, amberjack, how does a 12 kHz Tesoro ignore differentiate between aluminum and gold -- which seems to be your implication?

Steve

Agreed Steve. My point is you tell the difference by noting the variance in the VDI numbers which is much more apparent the higher the resolution, or higher number of target ID segments. I'm quite aware gold does read in the same range as foil/pull tabs etc.The difference is, on a detector with a high target ID resolution, a piece of foil may read from 1 to 22 where a piece of gold will ready from 1 to 3. But on a detector with low target ID segment that 1 to 22 could all be the same on gold so telling the difference is by digging.

Try it yourself. Take a piece of foil that reads in the same range as a piece of gold to test. Run it under a detector with a high target ID segment, like the DFX, and see how the numbers bounce wildly and with a high variance. Now take a piece of gold and do the same test. You'll see the numbers are far more consistent, the higher the target ID segments the more consistent, and a much lower VDI variance. Now do the same test with a detector with a low target ID segment like 20-30. You'll see little difference between the foil and gold. <--- my point.

 

[Jackpine Savage]

This can be frequency dependent as well. I have found that the X-Terra 705 with "only" 40 non-ferrous TID segments will provide wildly varying numbers on tabs and tab pieces yet lock fairly solid on nickels when run at 18.75 kHz. I hunt a site that was regraded some 17 years ago where old and new coins were effectively put in a mix master and deposited up to a foot deep along with the requisite trash. The X-T at the higher freq will hit nickels with a 2 number spread while beaver tails and pieces fluctuate much more in TID and usually with higher numbers. This on targets in the 6-7" range.

Hopefully the Equinox with its fast response will allow this in the audio alone without having to rely on TID numbers. According to one tester when running full tones the audio can be telling.

Tom

 

[Southwind]

I have found that the X-Terra 705 with "only" 40 non-ferrous TID segments will provide wildly varying numbers on tabs and tab pieces yet lock fairly solid on nickels when run at 18.75 kHz.

Exactly! This is what I'm trying to point out. Generally even with 50 or so target ID segments you can tell when you hit a nickel as compared to a piece of aluminum that may fall in the same range but bounces all over. You just can look at the more tight VDI of a nickel and say this is more than likely a nickel. Same with gold. If you find enough you start to see the same identifiable VDI response. The more target ID segments you have the easier it is to spot the good from the bad. With the 191, 95 conductive, a nickel is pretty obvious. As is gold if you pay attention.

 

[sgoss66]

I have found that the X-Terra 705 with "only" 40 non-ferrous TID segments will provide wildly varying numbers on tabs and tab pieces yet lock fairly solid on nickels when run at 18.75 kHz.

Exactly! This is what I'm trying to point out. Generally even with 50 or so target ID segments you can tell when you hit a nickel as compared to a piece of aluminum that may fall in the same range but bounces all over. You just can look at the more tight VDI of a nickel and say this is more than likely a nickel. Same with gold. If you find enough you start to see the same identifiable VDI response. The more target ID segments you have the easier it is to spot the good from the bad. With the 191, 95 conductive, a nickel is pretty obvious. As is gold if you pay attention.

Perhaps there are signatures you can pick out; I don't have a DFX nor any other machine with over 100 VDI segments. But on, for instance, a Gold Bug Pro (100 segments), a balled-up piece of foil, a folded beaver tail, an aluminum foil seal/disc from some types of drinks, a ring tab...MANY of those would register a very tight VDI range. But maybe the DFX is different, I can't speak on that. I've only had 100-segment machines...

Steve

 

[dewcon4414]

Lets hope that high freq gives us good separation in the lower digits like the Sov. If not we could get a lot of tiny gold sounding like minerals and we will be tuned to foil. This is where the CTX smear screen would come in handy....... Gold rings like their tones give a very tight picture. Most of the big stuff ..... over .3 grams we are already finding with multi freq machines. Everyone gets those awhaaa moments after digging a gold ring they didnt expect. So we hope to hit is some of the smaller stuff in that foil range..... or a bit more DEPTH on small gold period. Id like to see foil come in around that 3 digit with a bit more separation. As a water hunter i find a couple of rings every year....... it not so much those as the depth on them and chains im looking from with those high freq.

Dew

 

[Southwind]

a balled-up piece of foil, a folded beaver tail, an aluminum foil seal/disc from some types of drinks, a ring tab...MANY of those would register a very tight VDI range.

Yes you're correct. I didn't say it was a 100% cure, it just increases the odds in your favor to dig less trash and more goods.

 

[Jason in Enid]

a balled-up piece of foil, a folded beaver tail, an aluminum foil seal/disc from some types of drinks, a ring tab...MANY of those would register a very tight VDI range.

Yes you're correct. I didn't say it was a 100% cure, it just increases the odds in your favor to dig less trash and more goods.

I have found that the physical shape and/or orientation play a lot more into VDI spread than anything else. A certain silver ring will read like a quarter 100% of the time until you break it, then the reading goes to crap. Beat, bend and twist up a ring and it will read over large area until when it was perfect. Even taking a good condition, solid band ring and change its orientation from flat to angled to edge and it changes the readout and spreads the VDI.

 

[Southwind]

Take a piece of canslaw put it in the ground and hit it from all directions and note the VDI spread. Take bent up ring or put it at any angle you want and do the same. Note the different in VDI variance. Not going to be close to the same a good percent of the time. Now a tab with a bent flap or a piece of canslaw smashed thick and round will, in most cases, read a tight VDI, but there are far more pieces of aluminum, canslaw and tabs that won't. That increases the odds in your favor. Still not 100% of course, but it does swing the odds.

 

[Jason in Enid]

Take a piece of canslaw put it in the ground and hit it from all directions and note the VDI spread. Take bent up ring or put it at any angle you want and do the same. Note the different in VDI variance. Not going to be close to the same a good percent of the time. Now a tab with a bent flap or a piece of canslaw smashed thick and round will, in most cases, read a tight VDI, but there are far more pieces of aluminum, canslaw and tabs that won't. That increases the odds in your favor. Still not 100% of course, but it does swing the odds.

True, but when I'm hunting for gold I can't let myself start ignoring those targets just because they aren't as tight on the VDI. Simply because I have seen good gold targets spread, and junk aluminum very tight, I just dig it all above foil in the turf. At least until I give up and go back to silver hunting.