Mineralisation Identification

[madhatter]

Hi All
I read a lot about mineralisation in the ground and the effects it plays on detector's, but not much on how to assess wether your in low or high mineralised ground.
Is there any visible signs to look out for infield?
or
Is it more online research?
Basically...... ]
I am interested in knowing how you assess how highly or low mineralised the ground/area is you are working on?

Thanks in advance for your input :Y: :Y: :Y:

 

[roddosnow]

:Y: I am also interested in hearing the expert opinions on the above

 

[BigWave]

I'm no expert, but here's my two bobs worth:
1. Look for ironstone.
2. Try the magnet on the end of your pick and see how much it picks up.
3. Check the colour of the ground.
4. Check the colour of the quartz/
5. Look at the vegetation. Ironbarks are about the only tree that can thrive in very highly mineralised areas of the GT.
6. Run in fixed tracking, and see how often you need to ground balance.
7. Count the hot rocks that you find.
8. Count the false targets that you dig.
I've worked a few extremely hot areas that I'll never go back to with my 4500!

 

[Bullwinkle]

I'm definately no expert either, but agree with previous comments. To add to that, I have also observed that the interference from ground noise can vary in just a few steps and on certain days.

 

[stevewilko]

Hi all,

I have been considering why I would or should choose (on my GPX) to select Enhanced in contrast to selecting Hi- Mineral.

The Minelab manual reads Enhanced - "a soil timing"
For Mono coil - reducing most ground noise and the response of hot rocks.

The Minelab manual reads Hi - Mineral - "a search mode"
To stabilise the detector in highly mineralised soils.

I am not sure as to when ground noise is not mineralisation, although I have found buried dense carbon from burnt tree stumps reacting like a ground noise.

but I wonder when I should determine to select either as the best preference.

I try not to use any suppressor 'as is my view of the idea of these selections'
and try to run in Normal and General at all times, even if I wind back the rx gain and stabiliser,

 

[Moneybox]

It's very hard to identify heavily mineralised soil. I've just posted a video .... https://www.prospectingaustralia.com/forum/viewtopic.php?pid=349953#p349953 .... If you take a look at the soil there, there is very little to indicate that gold may be found.

About 100m from here there's a strip about 20m wide running through the paddock that upsets all PI detectors. It has nice signals indicating a nugget but everybody digs but nothing is found. This is evident of by the strip of open holes, some of them huge. Most people have been quite good at filling their dozens of holes nearby but in this strip they've left them open indicating to others that they are wasting their time digging. We watched a guy using a GPZ7000 give up and we've tried with the SDC2300 and GPX4500. The surface looks exactly the same and even when you dig, there's really nothing different to look at but the red dirt pulled from the hole sets off the detector the same as the bottom of the hole.

 

[tryhard1968]

I'm no expert, but here's my two bobs worth:
1. Look for ironstone.
2. Try the magnet on the end of your pick and see how much it picks up.
3. Check the colour of the ground.
4. Check the colour of the quartz/
5. Look at the vegetation. Ironbarks are about the only tree that can thrive in very highly mineralised areas of the GT.
6. Run in fixed tracking, and see how often you need to ground balance.
7. Count the hot rocks that you find.
8. Count the false targets that you dig.
I've worked a few extremely hot areas that I'll never go back to with my 4500!

Hey BW,

Can you let me know all the spots you wont go back to as I love those spots

 

[Ridge Runner]

Hi All
I read a lot about mineralisation in the ground and the effects it plays on detector's, but not much on how to assess wether your in low or high mineralised ground.
Is there any visible signs to look out for infield?
or
Is it more online research?
Basically...... ]
I am interested in knowing how you assess how highly or low mineralised the ground/area is you are working on?

Thanks in advance for your input :Y: :Y: :Y:

The easiest way to find out is to use a VLF Detector and use the meter on it, They will tell you how high the Iron content is, Also the meter will also show you where the black sand deposits are by displaying a high reading and that is where fine gold is normally found, and they will show what type of mineralization it is.

hope that helps,

John.

 

[BigWave]

tryhard1968 wrote: "Can you let me know all the spots you wont go back to as I love those spots"
Ask Dig'n-it how bad it was.

 

[PhaseTech]

Where you are pinging ground noise with the SDC - that is hot ground!

But yes, BigWave pretty much nailed it. Ground goes red because iron is oxidised.
Wikipedia says: "Yellow or red soil indicates the presence of oxidized ferric iron oxides. Dark brown or black color in soil indicates that the soil has a high organic matter content. Wet soil will appear darker than dry soil. However, the presence of water also affects soil color by affecting the oxidation rate."

So, blood red soils, with a healthy dose of visible ironstone on the surface you can be sure it'll be pretty mineralised. But there are other things that can make your detector go pear shaped like basalt, in seemingly non mineralised soils. The one time I was in Arizona I was working a creek and the colour of the dirt was quite pale, and looked pretty tame, but running a magnet through the wash indicated huge amounts of black sand!

The visual clues will give you a fair indication, but ultimately when you start swinging your detector, that will tell you the true nature of the ground.

 

[oldtimerROB]

My new detector has a mineralisation meter to indicate the level of mineralization you are detecting on.When the meter is full the detector overloads and you can,t GB on it. Moneybox,s patch is very interesting,I would call it extreme mineralisation,like walking on corrugated iron.Found a patch like that on top of a hill at Goldsborough 15 meters diameter and you can,t GB on it. I have a special mode on my detector for such mineralisation and I quickly GB,d on it but the wife got cold and we had to leave.I need to go back and see if there are nuggets there as I found two large ones nearby a few years ago.I found a gully at Havelock which had numerous patches like that only they were much smaller at one meter diameter.Apart from said mineralisation my detector is very stable without picking up ground noises but picks up hot rocks which I get a low iron tone with, and the smooth small brown stones which give a high tone along with the pieces of charcoal.

 

[Ridge Runner]

I think most detectorists know that Red Dirt means trouble, It's pretty common knowledge.