What is this bedrock signal??

AU79 Prospector

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I posted this video awhile back.... but as I review my videos, I can't help wonder -- what the heck was that signal? For background, this exact area has produced big nuggets (16 grammer found 10 yards up stream, 2 grammer found within a few feet). Fast forward to time 2:10 to get to the point of interest. I couldn't find a crack.... or a nugget. Was it hot bedrock? None of the other bedrock there was hot like this... I'm a novice detectorist so I'm trying to learn a bit.

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Jim Hemmingway

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Hi AU79 Prospector…

That was quite a strong, discrete signal captured in the video. I presume that you thoroughly removed and broke-up the bedrock producing that signal. So what happened to it… did the signal just peter out as you broke-up the material?

Given that was the case, and in the absence of recovering a metallic target, we’ll have to conclude that the signal was produced by some unidentified mineral anomaly in the bedrock. Interesting because such occurrences normally produce broader, less distinct VLF signals than those produced by a typical small nugget. At least that has been my experience here in northeastern Ontario.

Thanks for posting the video, it was nicely produced, interesting too with that intriguing signal. :)

Jim.
 

bug

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Signal sounds well defined. Id definitely hammer and chisel away after finding the tip off color in the same pocket. Here in California we have to chisel em out, as the nuggets can be well embedded deep in the cracks.
 

Hoser John

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Tap with a rock hammer and listen for a hollow sound. Many minerals will have voids. Coffee creek in trinity county is one, tap tap and a smash bash and viola gold-John
 

IMPDLN

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First I would check it with a magnet to see if it might be an iron pocket. If not magnetic it's chisel and hammer time. I found a silver seam in bedrock once that way. Took too long to recover as that bedrock was hard grey and smooth, but I had fun finding out what was giving me a signal. Dennis
 

Lanny in AB

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Well, I've listened to the signal, seen what I could of your bedrock from what's visible on your video, but this I'll have to say: your detector hit on a metallic signal, so as the others have said, I certainly hope you cut into the bedrock and carefully broke it down to see what the signal was.

Last summer I ran into the same thing, screaming signal coming from the bedrock (good nuggets all around) great signal on the Garret Carrot as well on the mystery signal, but I took the big hammer and the chisel and went to work. I had to go into the bedrock about seven inches, but I finally found what was generating the signal, and it was a pocket of black, decomposing native iron that crumbled to pieces in my hand.

On another note, I've chiseled many a sassy nugget from what looked to be solid bedrock with similar sounds to what you've got there, so I'm with everyone else that chimed in and I certainly hope you broke out the signal to see what it was. You never know until you go . . .

All the best,

Lanny
 

Jim Hemmingway

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Well, I've listened to the signal, seen what I could of your bedrock from what's visible on your video, but this I'll have to say: your detector hit on a metallic signal, so as the others have said, I certainly hope you cut into the bedrock and carefully broke it down to see what the signal was.

Last summer I ran into the same thing, screaming signal coming from the bedrock (good nuggets all around) great signal on the Garret Carrot as well on the mystery signal, but I took the big hammer and the chisel and went to work. I had to go into the bedrock about seven inches, but I finally found what was generating the signal, and it was a pocket of black, decomposing native iron that crumbled to pieces in my hand.

On another note, I've chiseled many a sassy nugget from what looked to be solid bedrock with similar sounds to what you've got there, so I'm with everyone else that chimed in and I certainly hope you broke out the signal to see what it was. You never know until you go . . .
All the best,

Lanny

Hi Lanny… without any experience with his area’s mineralogy, I can’t be confident just what produced that attractive signal. My experience is limited to the areas we search on the Precambrian Shield, and those areas are geologically different from gold placer areas in the western regions of the continent. Over here we commonly encounter a number of sulfides and arsenides of silver, copper, iron, cobalt, and nickel that produce discrete “metallic” signals similar to his signal. But as I say, none of this may apply to his area.

There’s no doubt that quite a small target produced his signal. And that target was very close to the surface, I’d say probably within an inch or so of his pinpointer. It might prove useful if he would revisit this thread and add any further observations as to what he did find in lieu of a small gold nugget or whatever produced that signal.

Frankly I wouldn’t know how to characterize the type of signal that might be produced by a small pocket of naturally occurring native iron, or possibly native iron mixed to some extent with nickel. I did some checking on the subject to learn that British Columbia and Oregon represent two of only a handful of sources globally where native iron occurs primarily in a basalt bedrock. Surface native iron is a rare occurrence because such material is so easily oxidized away over time. I like your suggestion in that regard, and seem to recollect that you have discussed such occurrences in the past on your thread http://www.treasurenet.com/forums/metal-detecting-gold/69-bedrock-gold-mysteries.html.

So what does all this mean? Well I think it was either a small gold nugget, a bit of lead or ferrous junk trapped in an obscure bedrock crack, or as you suggested perhaps native iron in the bedrock. It was such a terribly discrete signal that I have a hard time believing it was anything but a small metal target.

Jim.

PS: If it wasn’t such a cold boring winter over here, I doubt I’d even bother with this thread, given the lack of attention or interest by the fellow that initially produced it. It’s been real cold here for most of the winter to date, but never quite enough snow to safely go cross-country skiing or snowshoeing.
 

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Lanny in AB

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Hi Lanny… without any experience with his area’s mineralogy, I can’t be confident just what produced that attractive signal. My experience is limited to the areas we search on the Precambrian Shield, and those areas are geologically different from gold placer areas in the western regions of the continent. Over here we commonly encounter a number of sulfides and arsenides of silver, copper, iron, cobalt, and nickel that produce discrete “metallic” signals similar to his signal. But as I say, none of this may apply to his area.

There’s no doubt that quite a small target produced his signal. And that target was very close to the surface, I’d say probably within an inch or so of his pinpointer. It might prove useful if he would revisit this thread and add any further observations as to what he did find in lieu of a small gold nugget or whatever produced that signal.

Frankly I wouldn’t know how to characterize the type of signal that might be produced by a small pocket of naturally occurring native iron, or possibly native iron mixed to some extent with nickel. I did some checking on the subject to learn that British Columbia and Oregon represent two of only a handful of sources globally where native iron occurs primarily in a basalt bedrock. Surface native iron is a rare occurrence because such material is so easily oxidized away over time. I like your suggestion in that regard, and seem to recollect that you have discussed such occurrences in the past on your thread http://www.treasurenet.com/forums/metal-detecting-gold/69-bedrock-gold-mysteries.html.

So what does all this mean? Well I think it was either a small gold nugget, a bit of lead or ferrous junk trapped in an obscure bedrock crack, or as you suggested perhaps native iron in the bedrock. It was such a terribly discrete signal that I have a hard time believing it was anything but a small metal target.

Jim.

PS: If it wasn’t such a cold boring winter over here, I doubt I’d even bother with this thread, given the lack of attention or interest by the fellow that initially produced it. It’s been real cold here for most of the winter to date, but never quite enough snow to safely go cross-country skiing or snowshoeing.

Hi Jim,

It is a little frustrating not to have any further feedback about his original post.

The signal I broke out this past summer had a nice sound right from the get go right on the surface, but as I got deeper into the rock, the signal got louder and louder, but upon reflection, what you say about the signal in the video is certainly true with the source being close to the surface as that is what made his pin-pointer sound off like it did. (If I was trying to ID that signal, I would have broke out the entire chunk that was producing the chirp (verified its removal by scanning the remaining bedrock to ensure no more target signal), and then scanned the broken out portion to ensure the signal was indeed in it. Then I'd have carefully broken down (and I do mean carefully) the bedrock to see what it held.

About the signal I chased though, when I got close to the decomposed iron in the bedrock, that's when my pin-pointer started to chirp and warble. And, as we had found lots of nice nuggets that day, I really thought we were on to something, but it was not to be.

After exposing that signal, we went on to find a half-dozen other nice nuggets in the same area, the deepest being down four inches, and we had to chisel that one out of the bedrock as well, but it was held fast in a crack in the bedrock, but that crack was in no way visible on the surface.

All the best Jim, and as always, I appreciate your expertise,

Lanny
 

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AU79 Prospector

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Hey guys, I completely forgot about this threat (I really apologize.....) but REALLY appreciate the feedback. Let me give you more info..

This video was shot very close to an old hard rock gold mine in Virginia (One of the biggest ones in the US prior to the 1849 gold rush). Back in the day, prior to the discovery of the motherlode vein, a 9 pound nugget was found in placer washings... every year, people still find big gold here (several 1-2 oz nuggets and specimens in the last decade). I found a 6 grammer here last year... so yes, most definitely gold in the immediate area.

On that day, I did not have the right equipment to break open the bedrock... it’s is solid, so I needed a pointed rock hammer... all I had was a chisel and sledgehammer and that didnt get the job done. I am a 100% novice dectorist, so didn't really 'know' if it was a good signal or not. I have practiced with my 6gram nugget buried in different areas to get a sense, and it sounded like this... but I couldn't find a crack over the signal (the crack nearby ran away from the signal).

I kind of forgot about it (got distracted by that nice flake I found in the crack) and moved on... I know I know I should be shot... but I know that area has not been busted open since this video. I will purchase a pointed rock hammer and try and open it out next time I'm out there. I will post an update (video update if it's good!).

Thank you again for your expertise and feed back... and sorry again for my lack of attention.
 

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Lanny in AB

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Au79, Good to have some up to date feedback, and here's a tip that may lead you to more nuggets in the future: lots of time when I chisel a nugget out of the bedrock, there's no sign of a crack on the surface, no visible sign whatsoever. In fact, I'd call it a misconception that a person has to see a crack on the surface for there to be a nugget in the bedrock. I have far too many instances, including the one I've related above, where I couldn't find any indication of a crack on the surface, but the gold was in one deeper down regardless.

Now, I've thought about this quirk or phenomenon for years, and I've reflected on past nugget finds from bedrock, and I know that some of the first nuggets I ever chiseled out of bedrock were "cemented" into ancient cracks in the bedrock with a matrix that was the exact colour of the bedrock with no cracks visible anywhere; the whole surface of the bedrock looked rather like smooth ocean ripples made out of black bedrock! But many chunky nuggets were in the bedrock regardless; however, in that case, it was more of a mortar-like camouflage job that concealed the nuggets.

In other cases, I've chiseled nuggets out of the mother rock with no visible crack on the surface, and I believe that's from huge boulders bouncing down ancient channels, and as they bounced and smashed, I believe they opened cracks by sheer force, allowing gold to quickly drop in, and the cracks then snapped shut again as the boulders moved on. Add to that hypothetical event the fact that a nugget may have already been in a crack, and the pounding of the boulders simply pulverized and pounded away any sign of the original crack.

These are just a few theories, but whatever the true reason for nuggets coming from "invisible" cracks, they rest there regardless as I really don't know for sure how they get there, but there they are.

All the best, and let us know what happens,

Lanny
 

63bkpkr

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Hey AU79,
The first time I hiked into what I now refer to as "My Canyon" in 1963 the river was wall to wall, milk chocolate brown and boulders were bouncing on the bottom of the river. Really ground shaking heavy 'Bangs/Thuds" were coming from down deep in that heavy flowing water. I suspect this is what Lanny has then 'seen' in a rock or bedrock that did not even show a crack along with cementing as a mortar mixture would certainly cover a crack.

Best of luck with your hunting once the snows melt................63bkpkr

PICT0265.JPG
 

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AU79 Prospector

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Thank you for the insight... very helpful and inspirational!! Outside of a point rock hammer (plus a sledge hammer and chisels), anything you would suggest I bring along to help open it up? I figure a lot of patience may be needed...

Au79, Good to have some up to date feedback, and here's a tip that may lead you to more nuggets in the future: lots of time when I chisel a nugget out of the bedrock, there's no sign of a crack on the surface, no visible sign whatsoever. In fact, I'd call it a misconception that a person has to see a crack on the surface for there to be a nugget in the bedrock. I have far too many instances, including the one I've related above, where I couldn't find any indication of a crack on the surface, but the gold was in one deeper down regardless.

Now, I've thought about this quirk or phenomenon for years, and I've reflected on past nugget finds from bedrock, and I know that some of the first nuggets I ever chiseled out of bedrock were "cemented" into ancient cracks in the bedrock with a matrix that was the exact colour of the bedrock with no cracks visible anywhere; the whole surface of the bedrock looked rather like smooth ocean ripples made out of black bedrock! But many chunky nuggets were in the bedrock regardless; however, in that case, it was more of a mortar-like camouflage job that concealed the nuggets.

In other cases, I've chiseled nuggets out of the mother rock with no visible crack on the surface, and I believe that's from huge boulders bouncing down ancient channels, and as they bounced and smashed, I believe they opened cracks by sheer force, allowing gold to quickly drop in, and the cracks then snapped shut again as the boulders moved on. Add to that hypothetical event the fact that a nugget may have already been in a crack, and the pounding of the boulders simply pulverized and pounded away any sign of the original crack.

These are just a few theories, but whatever the true reason for nuggets coming from "invisible" cracks, they rest there regardless as I really don't know for sure how they get there, but there they are.

All the best, and let us know what happens,

Lanny
 

IMAUDIGGER

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Could be lots of things...little pocket of arsenopyrite, graphite, molybdenum disulfide, pyrite, ect.
Many times it will occur in a dike formation. I find lots of exciting sounds in bedrock (usually dark to black colored bedrock).
The mineral I commonly encounter will give off a sulfur smell when struck. Figure some sort of sulfide based mineral.
I have found lode gold associated with these types of conductive mineral deposits.
Usually a very strong signal which becomes dissipated as the bedrock is broken away.
I’d love to know more myself.

Long story short..you have to investigate but know when to walk away.
Just remember that mineralized bedrock might also be associated with a gold deposit.
Pack some home and crush it up pan it out. I’ve done that several times. Now I know to walk off when I get those types of signals in that black bedrock. Used to spend 30 minutes banging away at the bedrock thinking I was going to hit the motherload.
 

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IMAUDIGGER

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This is what I’m always thinking I will find...
716486D5-5FFD-4D66-89E8-09A27426932A.jpeg
 

IMPDLN

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A good quality cold chisel, preferably with a plastic guard to protect your hand, 3lb sledge hammer, gloves, safety glasses as chips will fly. A crevice tool can help once you expose whatever it is, and a blow straw to blow away any dust so you can see into the excavation. Look at the rock and find the direction of the grain. Just like splitting wood, you want to work with the grain. Of course as I mention above, check it with a magnet 1st. If a super magnet sticks to the rock it is likely just an iron pocket. However I would still try to expose it to be sure even if magnetic. After all, iron is the mother of gold. Also make sure you bring your detector or pin pointer or both so you can tell if the signal gets stronger or dissipates as you go. Hopefully it gets stronger as you get closer to it. It will be a learning experience, but there is only one way to be sure. Dennis
 

Ballarat Bitter

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Where I go looking for nuggets, charcoal from past bush fires, and small hot rocks produce good signals. Other less distinct signals which I spend a lot of time digging up are false signals caused by localised mineralised anomalies.These can be partially averted by reducing the gain but then depth is lost and small gold nuggets or very deep ones may be missed. The only time I get a good metallic signal is if the metal is sitting on the ground and the VLF screeches.It is a juggling act when searching for nuggets on goldfields and the most demanding type of detecting.It could take 12 months of frustrating searching before a find is made. I have found big nuggets in the past-2 to 3 ounces and they were easy to find for the simple reason they were there. Nowdays they are very rare.
 

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Assembler

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Where I go looking for nuggets, charcoal from past bush fires, and small hot rocks produce good signals. Other less distinct signals which I spend a lot of time digging up are false signals caused by localised mineralised anomalies.These can be partially averted by reducing the gain but then depth is lost and small gold nuggets or very deep ones may be missed. The only time I get a good metallic signal is if the metal is sitting on the ground and the VLF screeches.It is a juggling act when searching for nuggets on goldfields and the most demanding type of detecting.It could take 12 months of frustrating searching before a find is made. I have found big nuggets in the past-2 to 3 ounces and they were easy to find for the simple reason they were there. Nowdays they are very rare.
Wonder if the fires and then the run off causes un-burned minerals to form little pockets or localized mineralized anomalies? Just like in some old camp fire pits.
 

bc5391

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I posted this video awhile back.... but as I review my videos, I can't help wonder -- what the heck was that signal? For background, this exact area has produced big nuggets (16 grammer found 10 yards up stream, 2 grammer found within a few feet). Fast forward to time 2:10 to get to the point of interest. I couldn't find a crack.... or a nugget. Was it hot bedrock? None of the other bedrock there was hot like this... I'm a novice detectorist so I'm trying to learn a bit.

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do yourself a favor and sell that Noka. Your buddy with the Equinox has a great machine. I had a noka, spent 2 hours digging around a bolder before I realized the bolder was the hot rock. The noka could never filter out hot rocks here in AZ, my new equinox has no problems (same area).
 

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