How to find all the things.

[Drack]

I'm having a hard time sorting through information on metal detectors and was hoping some people might want to answer what they would do for a vague scenario.

You are on acres of land that has metal and treasure everywhere at many depths in many geological conditions. You don't know which metal type you are going to pull from the ground until you are done but will map the locations. You can pass over the land once with each detector type in any specific setting, if you change the settings you can pass over the land with the same detector again. What detectors would you use to determine all the treasure type and location as quickly as possible and why? Bonus points for frequency specific coils.

Seems to me I would want a VLF detector that would miss the majority of non ferrous/small items and then pass over again with a pulse induction unit with discrimination for non ferrous treasure. If you had everything you needed to do it all what would your list look like?

[Skippy]

"Seems to me I would want a VLF detector that would miss the majority of non ferrous/small items"
No .... you definitely don't want to miss the small non-ferrous items , they can be just as worthwhile as the larger items.

Why are you mapping the find locations? Is this an archaelogical survey ? In which case you should be recording all finds, including iron.

Good all-round VLF machines that are popular are:
XP Deus; Minelab Equinox 600 & 800; Nokta-Makro Impact & Multi-Kruzer; Minelab E-Trac & CTX3030

[Drack]

I don't have any specific projects planned. I am more interested in mapping huge swaths of land with points of interest. Basically I would like to scan land once to map it if possible but would go over it again to make sure nothing was left out. I'm actually more interested in using the data gleaned with Ai and mapping algorithms. What equipment would you use to cover finding meteorites to gold chains with the least amount of passes to find it all?

[Skippy]

Meteorites AND gold chains ? That's a wierd combination. Sorry, I can't help with either of these, we don't hunt meteorites in my location, and gold chains might be found on the beach, but only if you're lucky, and I don't detect the beach.
The 'Detector Prospector' forum has a section dedicated to meteorite hunting, that may be worth taking a look:
https://www.detectorprospector.com/f...or-meteorites/

[kt315]

you can buy a book VOODOO on Amazon. its PI with disc.

[Drack]

Wouldn't the voodoo not go very deep?

[kt315]

Meteorites, gold chains, very deep... That's a wierd combination

https://www.youtube.com/watch?v=vv5gemp6cnA

[Skippy]

Mr. Drack is clearly not a detector user, and has no idea what he wants, or what is achievable, or realistic. And he has no idea about the items typically buried in the ground. Dreams of ground being full of 'treasure' is laughable. Ground is full of garbage and rusty iron crap like nails. Finding 'treasure' is a rare thing, even if it actually exists, because it is outnumbered thousands of times by garbage.
Then saying he want to 'eliminate' small non-ferrous items, then later saying he wants to find gold chains ? Gold chains ARE small items, very very small items, that are VERY hard to find, most of the ones found ( on a beach ) are discovered because they have a larger pendant/cross/medal/St Christopher etc on them, or a large fastening clasp. The chain itself is almost invisible.

[Drack]

Skippy, you're half right. But I am no means dissolutioned and think there is treasure everywhere. I doubt anyone has made a profit over a job with their metal detector not working an actual gold claim. What I want is to know a list of equipment that you would use to find all the things over acres of land Trash and not. I would of hoped you would of answered the scenario. As of right now so far pi metal detector is the only thing someone would use to find all the things. Seems lackluster and probably not the only equipment they would use to actually find all the things.

[Skippy]

Unfortunately, most PI machines are generally weak on very short time-constant non-ferrous targets. This means tiny nuggets, gold chains, bits of aluminium foil, gold earrings, etc, things that read low-down, where 'foil' is often shown on detector ID screens. There are machines specifically optimised for such targets, particularly the GPX / GPZ range of nugget-hunters made by Minelab, though Whites also made some good machines, and there are a few others, like the 'QED' machine. But these are very expensive, and not really considered 'general purpose' detectors. They would be nearly useless on European farmland, where thousands of years habitation has left the ground full of metal, 100+ targets per square metre.
But if you are exploring wild open spaces, where there has been little human activity, then a machine like a GPX-series would be your best choice.

Coil size choice is also important. Smaller targets are best found with smaller coils. Large targets with large coils. The typical coil, of 20 - 25 cm diameter that many machines are used with, is a general purpose size, that will be OK for the typical sizes/compositions of targets that are wanted from parks, fields, beaches. But if you were specifically trying to find small nuggets, or tiny jewellery, or tiny ancient coins, a smaller size, like 10 - 15cm would get better depth.

You should be aware that many locations have naturally-occurring rocks and stones that will give a signal to a metal detector. They are sometimes called 'hot rocks'. I can find them here in England, my examples are slightly magnetic, brown coloured, and clearly contain some iron oxides. But they are worldwide.

[Drack]

So you would use a GPX / GPZ minelab detector and pass once with a 250mm coil and again with a 100mm coil. Seems like you would not "find all the things". Considering a 1 meter coil could be used for deep things and all. But it looks more probable than the other option that "found all the things" with one pi detector and coil.

[Skippy]

That would probably be a reasonable plan. You should have a good look on Minelab's website, there are many pages of information about how to use these machines, how to choose the best settings/adjustments, the best coil size.
There are some relevant guides here, too:
https://www.detectorprospector.com/m...steves-guides/

[Koala]

cant be done

You can dig out all no ferrous targets in an area you carefully grid

you can then grid the same area at 90 and dig more none ferrous targets

you can go back over the next day and find more from the same area

you can go back with a different coil size and find more again

you can go back with a different coil type and find more again

you can go back and remove all ferrous targets and you will also find some more none ferrous

you can go back the following year and find some more

there are some small fields that have had a rally on them year in year out and are still finding targets

but you can't sweep once without digging and be even close to mapping every artefact unless the field has been sanitised and targets added

you can map areas of concentration. But even then it will not tell you gold chain. The best discriminator is a spade

[Skippy]

What he's trying to do will work OK if there are few targets, and they are spaced apart enough. But once the target density increases, you're going to find 'masking' , where one target hides the presence of another, for example a tiny nail 2cm down obscures a large silver coin 10cm down below it. Or vice-versa, a 1kg steel plough/plow blade at 30cm stops your detector seeing any small target above it over a 40cm diameter circle.
Articles about 'masking' , by Tom Dankowski:
http://www.dankowskidetectors.com/behindthemask.htm

http://www.dankowskidetectors.com/painful_truth.htm

[Drack]

I suppose if you were to find all the things you would start with a minelab unit make a pass with low intensity settings. Remove all the things and increase intensity and repeat until you no longer find things? Or would you start with high intensity and work down to a lower intensity?