Need advice on electronic gold detector


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Hello

I need some advice from the detecting crowd as I know nothing at all about detecting for gold.

I am attempting to work with an on again, off again beach gold (and possibly platinum) placer deposit. One part of the deposit is an 8" deep lens of pure black sand that gets left by the Pacific storms that frequent us. I've had two samples of this assayed; one came back very rich and one had nothing at all. Later investigation showed that the flaky flour gold actually settles down through the beach and is caught (hopefully) on a clay hardpan below. I've dug down to this hardpan but have not had a sample assayed. However, considering the number of waves in a storm and the number of storms we get, it could be a VERY rich deposit.

The problem with the gold is that most of it is likely in the 200 mesh size range. Looking at the hardpan, once uncovered, it looks like nothing but a layer of clay although one could be looking at a vast amount of gold and not even see it. This rules out panning a sample for evidence of gold, unless you are a super panner, which I am not. I've looked at a couple of gold test kits (leaches) but have been told they don't work very well. What I am looking for is something that will indicate the presence or absence of gold so I might put further effort into concentrating and recovering it.

Someone suggested a metal detector of the type used to find gold. I would be baring the beach down to within an inch or less of the hardpan before I tried using it. Can these things be tuned so they will only detect gold and ignore all the iron in the black sand and other base metals? Will they detect microscopic gold if there is enough of it together in one spot? Will a small concentration of gold give a small signal and a large concentration give a large signal?

Thanks in advance for your consideration.

Regards

Bob

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Traveller,

Flowergold is to small to use metal detectors on.

Best thing to do is dig up some clay you think has gold in it and let it dry....you then could put the dryed clay in a cement mixer (with rocks or steel balls) to break up the clay.

Take the powdered clay and process it (shaker table, panning or blue/green spiral wheel) & see if you get any flowergold.

wonderer

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Won't work!

There is no metal detector I know of that is going to assist you in locating gold of the nature you are discussing.

Now something you might try, and it would not be very inexpensive, is to use a FALCON Gold Probe. They are $219.95 I believe that's what we sell them for.

They hit on the smallest gold I have ever seen, and they do have a unique feature to determine whether you are hitting on gold or black sand.

When you pump the probe back and forth against the ground, if you hear a louder sound when pulling the probe back from the ground, than going towards the ground, it is mineralization, if the sound is louder going towards the ground it is more likely to be gold.

I don't even think a Fisher Gold Bug would help you in what you are trying to accomplish.

Doc

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wonderer and DOC

Thank you for your excellent advice.

Wonderer, I have actually put together a basic Miller table to test samples of this clay at home. Hopefully this will give me an indication of volume of gold present in a given area of hardpan, should I locate material suitably rich to work with.

However, the beach where this placer resides is a long ways in and it would be nice to know, roughly, if there is enough gold present on the hardpan to make it worthwhile to take some of it home.

DOC, the MD20 seems to be exactly what I had in mind. Although I said in my first post that I would bare the beach down to within an inch of the hardpan, it would be no trouble to place the MD20 probe directly in contact with the hardpan surface.

There seems to be a significant amount of pyrites and mica on the hardpan, as well. Will the black sand/gold distinguishing feature of the MD20 work on this material?

If there were enough flour gold on the hardpan that it actually formed an almost solid layer, would a detector see this as a larger piece of gold? The reason I ask is this; the positive assay I had done on the black sand sample from the surface of the beach came back at .32 oz./ton. With the sample being almost pure magnetite (hematite and garnets are deposited lower on the beach) having a sp. gravity of 5.5, this works out to roughly 1.5 oz./cu. yd. However, as I mentioned, due to wave action, the gold does not seem to stay long in the black sand; choosing to migrate downward to hardpan. If I am digging hardpan at the lower toe of the beach, I am likely excavating what was the upper beach (magnetite) zone from twenty years ago; from landmark observation studies. Therefore, if there are a few thousand waves during each storm, and we average fifteen good storms over a winter, and we multiply this product by twenty years, the total accumulation on the hardpan could, quite literally, be staggering. Would a detector give any different kind of signal if this were the case?

Regards

Bob

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Traveller,

I've heard that people have tryed to use flowergold in a vial (say 1/10 OZ. from paning) as a test for their metal detector & it did'nt work. But if they melted it to a blob it was detectable. Haven't tested this out (flowergold issue) though myself as I don't pan, drywash or dredge.

People even have issues detecting (parks and playgrounds) small gold metal chains like girls like to wear because the small links don't take a hit (or give a signal) like a larger solid gold object.

Unless your test pans for the beach have gold pickers in them forget using a metal detector to detect patches of flowergold.

I had the Falcon Gold Probe model before this new one & was'nt impressed with it, maybe the new one is better. Think they make it in Mesa, AZ., + I don't know if it works on wet beaches & around salt water well. You might have to call the manifacture & find out.

wonderer

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Bob,

I have a Falcon MD10, the predecessor to the now Falcon MD20, I have not tried it on fine gold, but it will hit on 2 to 3 grain gold, you will have to almost touch the gold at this size for it to detect it, even on larger gold you need to be within 1" to 2" for a signal, but it is designed as a pin pointer that is why you need to get close for the signal.

I would suggest that you contact the manufacturer, he will be able to answer your questions, I contact him via email when I got my used MD10, as I thought it wasn't working right because of having to get so close before it would give a signal, he didn't answer my email but instead called me, I was surprised as most wouldn't call just play email tag with a customer, I was more surprised because I didn't buy the MD10 new from him or a dealer, anyway I was glad that I included my phone number in my email, and I appreciated the personal touch of a phone call.

Here is a link to the Falcon website, it has contact info at the bottom of the page.

http://www.falconmetaldetectors.com/

If you do get a MD20, be sure that you don't get the control box wet at all, all the rest is water proof, unless you get a nick in the probe wire, also when not using it for any length of time to be sure to remove the batteries to avoid having them corrode within the box.

Edit: I just found their phone number as well if you prefer to call instead. (480) 396-1181

Also here is a link to the MD20 owner's manual if you would like to read up on it's operation.

http://www.falconmetaldetectors.com/sitebuildercontent/sitebuilderfiles/MD20MANUAL

Skip

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Pyrite and Mica does not affect the MD20. There are a lot of guys who are extremely successful sniping with the Falcon Gold Probe (FGP). Instead of prying open every crack in bedrock, they scan the crack first with the FGP to determine whether it is worth their effort to bust the crack open and vacuum the contents out for later panning. I have heard reports and met one guy who had found some pretty darn nice nuggets.

If you had a solid layer of gold, yes you might get a hit from a VLF detector, however, with the amount of black sand you are talking about you would probably have a heck of a time figuring out which is which. The Minelab pulse induction machines just won't give you a hit on gold unless it is a solid contiguous piece. I have seen many a perplexed new Minelab pulse induction owner complain when they threw down a large vial of 3 ounces of gold dust and said, "What the hell is wrong with this machine it won't even pick up three ounces of pure gold."

Well the problem is the Minelab's are so good at balancing out mineralization, that really fine gold looks too similar to mineralization and the Minelab balances it out as well.

What you are describing on your beach is the world's largest gold pan. That wave action has just allowed that gold to drop straight down to the hardpan which is like the bottom of a huge goldpan, now the only problem is finding out where on the bottom of the gold pan did the gold end up settling?

Is there a contour to the beach? Any place where the water has a tendency to "channel" back into the large body of water? Any out croppings of rock?

This almost seems like a job for ground penetrating radar. You know there is gold there, you just need to know where there is a likely concentration of it. I am thinking GPR might show you the depth and contour of hardpan. Any high spots in the hardpan that run parallel to the waters edge would act like a riffle in a gold pan to trap the gold.

What is the depth of sand before you get to the hard pan? Could you drive pipes into the sand and into the hardpan and take samples to give you an idea of where might be the most profitable area to invest your time?

Sounds like it will be interesting, maybe a little frustrating and possibly very exciting.

Good Luck!

Doc

wonderer and DOC

Thank you for your excellent advice.

Wonderer, I have actually put together a basic Miller table to test samples of this clay at home. Hopefully this will give me an indication of volume of gold present in a given area of hardpan, should I locate material suitably rich to work with.

However, the beach where this placer resides is a long ways in and it would be nice to know, roughly, if there is enough gold present on the hardpan to make it worthwhile to take some of it home.

DOC, the MD20 seems to be exactly what I had in mind. Although I said in my first post that I would bare the beach down to within an inch of the hardpan, it would be no trouble to place the MD20 probe directly in contact with the hardpan surface.

There seems to be a significant amount of pyrites and mica on the hardpan, as well. Will the black sand/gold distinguishing feature of the MD20 work on this material?

If there were enough flour gold on the hardpan that it actually formed an almost solid layer, would a detector see this as a larger piece of gold? The reason I ask is this; the positive assay I had done on the black sand sample from the surface of the beach came back at .32 oz./ton. With the sample being almost pure magnetite (hematite and garnets are deposited lower on the beach) having a sp. gravity of 5.5, this works out to roughly 1.5 oz./cu. yd. However, as I mentioned, due to wave action, the gold does not seem to stay long in the black sand; choosing to migrate downward to hardpan. If I am digging hardpan at the lower toe of the beach, I am likely excavating what was the upper beach (magnetite) zone from twenty years ago; from landmark observation studies. Therefore, if there are a few thousand waves during each storm, and we average fifteen good storms over a winter, and we multiply this product by twenty years, the total accumulation on the hardpan could, quite literally, be staggering. Would a detector give any different kind of signal if this were the case?

Regards

Bob

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How come the Falcon pinpointer isn't built in to a metal detector, so you can just flip a switch? ;)

I was just in a very trashy wash- lots of rusty metal in cement-like dirt but you can access the soil layers and get down to bedrock.

I wonder if a Falcon would be good to use as a detector in that environment.

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I think it would be a great asset for some prospectors. But others would not care. Personally I don't work a lot of areas where I run into bedrock, so my use of a probe is pretty limited.

Rob carries the Coiltek probe, where all you have to do is plug it into your detector, plug your coil into the probe switch box, and when you need the probe you flip the switch.

Doc

How come the Falcon pinpointer isn't built in to a metal detector, so you can just flip a switch? ;)

I was just in a very trashy wash- lots of rusty metal in cement-like dirt but you can access the soil layers and get down to bedrock.

I wonder if a Falcon would be good to use as a detector in that environment.

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The gpaa has developed some good methods for recovering beach gold...

as for the hardpan clay...break it up on-site and pan it carefully...I would use the garret gravity trap gold pan, there may be better pans out now. This is the best and lowest tech way to get the info you want...it does require some manual labor though...

Fred

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Rob carries the Coiltek probe, where all you have to do is plug it into your detector, plug your coil into the probe switch box, and when you need the probe you flip the switch.

Doc

Thanks, Doc.

I'm happy with the very small targets the 5000 is revealing.

I just got back from another trashy area and I think a gold detector would be a good addition to my tool kit.

Also to know whether it's worth busting into those crevices.

Yesterday I saw a spot where someone did quite a bit of digging to reveal a metal strap 2 & 1/2 feet or so deep. It was accessed from the side in a wash so it's kinda fun to see how the detector responds from the top and sides.

I'm still referring to the manual and trying different settings.

If Rob doesn't have the pinpointer I'd like I notice you're a Falcon dealer so we might do some business.

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How come the Falcon pinpointer isn't built in to a metal detector, so you can just flip a switch? ;)

I was just in a very trashy wash- lots of rusty metal in cement-like dirt but you can access the soil layers and get down to bedrock.

I wonder if a Falcon would be good to use as a detector in that environment.

The older Falcon had a accesory extention handle (& optional nylon web belt holster(for easy carry)) so it could reach down into crevices or be used standing up, say on bedrock . . don't know if the newer one has the same options.

wonderer

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DOC

I was discussing the Falcon MD20 with a number of placer miner types on another site and they mentioned the manufacturer's claim of being able to detect pieces of gold as small as 2/100th of a grain.

I understand that detector operators typically refer to the weight of their finds as most are individual discoveries. However, this group I was chatting with were wondering if it would be possible to give a reference in mesh size; something they are more familiar with.

Regards

Bob

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DOC

I was discussing the Falcon MD20 with a number of placer miner types on another site and they mentioned the manufacturer's claim of being able to detect pieces of gold as small as 2/100th of a grain.

I understand that detector operators typically refer to the weight of their finds as most are individual discoveries. However, this group I was chatting with were wondering if it would be possible to give a reference in mesh size; something they are more familiar with.

Regards

Bob

There is nothing on the manufacturer's website that states that it will find gold as small as 2/100 of a grain, I would guess that is a rumor and nothing more, gold in it natural settings has to many different variables and a statement like that would be bad business for any manufacturer to make without repeatable proof, and if the manufacturer had that proof, you can bet it would be on the website as a selling point.

As I mentioned I haven't tried my MD10 on any fine gold, I will try to do some testing in the next week or so, I can't do it this weekend because of having to work, when I get some results I will post what the MD10 can do in mesh size.

Skip

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All I can tell you is that the manufacturer gives you a piddly little speck of gold taped on a business card as a test piece. It picks it up. I have a piece of conglomerate with a couple of specks of gold in it. So small that people can not see it unless you point it out and even then they have a difficult time unless you give them a 10 plus loop. And the Falcon hits on it.

I have no idea how much the test piece weighs but it is nothing a detector would ever see. Now granted, you are running the test gold directly on the probe.

Doc

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If you will pay for the shipping I will be happy to send you mine so you can try it out and see if it works first. I hate to see you spend money on it if it is not going to do the job.

Doc

DOC

Good points you are making. I guess it is just one of those situations where the only way to determine the effectiveness of this unit is to buy one and try it out.

Bob

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DOC

This is a very generous and trusting offer you are making to me. May I say here, that I am deeply honoured by the trust you are placing in me and, should you lend me your detector, I vow it will receive the utmost care for the time it is in my possession.

I will contact Canada Post and enquire into the cost of return postage from Nevada, USA to British Columbia, Canada.

Could you tell me how much the MD20 weighs and approximately the size of the box it would be shipped in?

Once again, thank you. As we are fond of saying here, "You are a gentleman and a scholar and a damn fine judge of horseflesh. I am in your debt always." :P

Bob

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The box would not be very large at all I think I can get it into a Priority Mail Small Flat Rate Box.

Tell me where you want it sent. Email me at cop704@yahoo.com

Doc

DOC

This is a very generous and trusting offer you are making to me. May I say here, that I am deeply honoured by the trust you are placing in me and, should you lend me your detector, I vow it will receive the utmost care for the time it is in my possession.

I will contact Canada Post and enquire into the cost of return postage from Nevada, USA to British Columbia, Canada.

Could you tell me how much the MD20 weighs and approximately the size of the box it would be shipped in?

Once again, thank you. As we are fond of saying here, "You are a gentleman and a scholar and a damn fine judge of horseflesh. I am in your debt always." :P

Bob

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I have had a MD20 for a couple years.I have it with me everytime I go out. It is great for determining if the rock you are looking at has ANY gold in it.The piece of gold on a card that they give you with the MD20 is the size of a pin point.I got the carry case ,it protects it .The manufacturer is very good about helping you with any problems.It finds gold so tiny there are times I couldn't see it.

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