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VLF Frequencies For Bigger Gold ?


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From what I can gather, higher frequency VLF detectors are more suited for smaller gold but ground mineralisation may be something to factor in. Would there be a “better” frequency for nuggets 1 gram and above in heavy ground?

I’m not too concerned if I miss sub gram nuggets if there is a better suited frequency.

The old Garrett Groundhog circuitry was legendary in this country…..I think it was around the 15 kHz mark. Is this frequency range a good starting point or do I need to consider other things such as better ground balancing capabilities or Garrett’s extra coil voltage. 
My Minelab PI units will be mainstay detectors but as mentioned in another post, I have ground littered in man made iron junk and the ground mineralisation is severe. There are plenty of nuggets in the 1 gram to 5 gram range (maybe bigger) but the iron signals are as dense as 5 per square metre 🤬

 Thanks for any ideas.

 

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Tony, 

IMHO

Depending on your ground, most 20 kHz and lower frequencies are better at handling the more mineralized ground conditions. That’s why I use the Equinox 800 in heavily mineralized ground as it gives you a single 20 kHz frequency for hot ground or you have the multi-frequency option for less reactive ground when looking for smaller gold. It also has some really good discrimination abilities for trash sites. If any 20 kHz or lower detector doesn’t work in your ground then I would recommend a PI machine at that point. 

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Equinox 800 gets all the vlf glory these days but the Gold Bug Pro (19 kHz) with the 11" DD has been my best gold detector in iron infested trashy mining sites .........still to this day.  Just love the simplicity, depth, ergonomics and very effective discrimination.   

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1 hour ago, NV-OR-ID-CAL-AU said:

Tony, 

IMHO

Depending on your ground, most 20 kHz and lower frequencies are better at handling the more mineralized ground conditions. That’s why I use the Equinox 800 in heavily mineralized ground as it gives you a single 20 kHz frequency for hot ground or you have the multi-frequency option for less reactive ground when looking for smaller gold. It also has some really good discrimination abilities for trash sites. If any 20 kHz or lower detector doesn’t work in your ground then I would recommend a PI machine at that point. 

Thanks for the great information……I might just take out what VLFs I have and see how we go……not dedicated nugget machines by any stretch of the imagination but worth a spin. 6.59khz and 13.8khz here we come.

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48 minutes ago, Chet said:

Tony

When detecting in trashy areas, gullies and desert washes I frequently carry a VLF along with the GPX 5000, GPZ 7000 and now with the GPX 6000. If roaming large areas of desert with only an occasional bullet or boot tack to contend with the VLF is left in the Jeep.

Over many years as VLF detectors improved the models for this purpose were upgraded from the early Goldmaster series to MXT to GMT to Gold Monster to now to a Equinox 800. All equipped with the smallest coil available. 

When a target is detected in a trashy area with the Large PI coil it is quickly pinpointed and discriminated with the VLF. If is too deep to detect with the VLF it gets you pumped up a little thinking that this is something good. As the hole gets bigger and deeper the small coil on the VLF pinpoints the direction to dig. 

Sometimes a dozen plastic knives with bright colored surveyors ribbons tied around them are used as markers. Detect the area with the PI. If a shallow loud target is detected lay a knife over it. If it is a weak low broader signal place the blade into an upright position. 

Lay the PI down and detect each marked target with the VLF. The shallow loud ones are fast and easy. The deeper ones require some aggressive digging to get the VLF close enough to detect, pinpoint and discriminate.

From years of experience with many detectors has led to this determination. The Equinox 800 with the small coil is the best, simplest automatic detector for this work and/or for stand-a-lone gold detecting. It has a build in pinpoint mode that immediately gets you on top of the target. Once on top you punch it back to discriminate mode and one or two sweeps you know whether it is ferrous, nonferrous or a hot rock. The target number read-out is so much better than the Gold Monster bar graph. 

Like most modern highly sensitive VLFs built for gold detecting it will sound off on many hot rocks. But it will have a repeatable number read-out that will correlate to the normal hot rocks produced in that area. 

Have a good day,

Chet
 

Chet…..awesome information as well. I’ll be putting these ideas to the test in coming weeks. I’m pretty handy with a PI but have to admit that I have never nugget hunted with a VLF…..although have heard of those that persevered back in the day when that was all that they had to swing. Small coil and low GAIN……

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If you are hunting gram plus nuggets in dense ferrous trash, any detector with a good reputation for relic detecting in trash will do the job. The XP Deus or ORX are top contenders, and offer different frequency options in one machine. Equinox is extremely close but maybe just a hair behind the XP offerings for working in dense ferrous. Once you get past XP and the Equinox there are dozens of good machines that all might serve as well, the key being small coils and lots of patience. I would say I was not impressed with the Gold Monster in dense ferrous, too many weird signals. The 19kHz Gold Bug variants all do better in that type scenario, and for the price are very hard to beat.

You list the MX7 as a detector you own, and it with a small coil would be the first go, before actually buying anything. It’s an excellent detector. You’d be surprised also at how many people use an Excalibur in ferrous. It suffers from masking, but excels at killing ferrous signals.

Out of the machines I currently have on hand I’d probably grab my Equinox for the task. Here is a link to some testing I did a few years ago. Main thing to take away is that most machines are up to the task, and the differences in most cases are rather minor. The real key is a small coil and knowing your machine very well, which is why I’d grab my Equinox. I’ve so many hours on it now it just talks to me in a language I can easily understand. 

 

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Tony,  I agree with Steve…….your MX7 with the 6” Detech DD coil or something similar in its prospecting mode or with a 2 tone ferrous/non-ferrous discrimination mode would work fine in iron trash on shallower .5 gram and bigger nuggets if it can handle your mineralization. 

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Thanks all……I agree the MX7 is worth a shot. Based on the MXT circuitry might be okay but I have heard that the MXT can struggle in bad ground…..but I’m talking bad ironstone ground. I may have to switch out the 6” Concentric coil to a smaller DD as Jeff suggested. Failing this then it’s time for a 6” coil on my 3500…….so long as the smaller coil/windings don’t get lit up by the hot ground. 👍

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