Ok, I cleaned them! Is the source that far away??


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Hello All,

Here is the cleaned pictures I promised. I think they turned out beautiful. Yes, the GPZ 7000 loves this type of gold, especially at depth. That being said, the GPZ really like all gold. I'm finding solid pieces, specimens and ironstone stuff I missed before.

So what do you think, the source is nearby?

post-2-0-43251700-1441678628_thumb.jpg

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I thought I was seeing things on my gold nuggets but in your Facebook post you mentioned "blue quartz". Now I know what you mean about that stuff. The quartz attached to some of mine likes to take on a blue hue also.

And one of the little ones I found at Rich Hill has a little of that purple quartz aka Amethyst on it as well.

That's definitely some eluvial looking gold you got there, the vein is probably close by.

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Hey Guys,

Yes, there is Blue Quartz on a few of the larger pieces, some ironstone, some typical white dirty quartz and a small portion of pink quartz (some call it Rose Quartz) on the long piece. In the Northern Bradshaw Mountains, the gold is associated with Gray or Blue quartz beyond the normal white. I have also seen some beautiful Rose Quartz specimens found. I personally think it depends on the minerals available and temps of the melt or cooling. All this can alter the color of quartz.

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I think you are close to the source Rob. Some of those pieces are very delicate and really could have not moved far. All the pieces have a lot of fine detail that would have broken off if they had moved a distance.

Doc

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By the way, wait until you start using that detector with the new Gold Screamer cover you just put on the control box! It makes the GPZ7000 much more sensitive and gives you another 20% more depth. :P

Doc

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Great looking specimens Rob !

I have learned alot in the last few years regarding source dynamics or locations. Boulder Dash has been a major influence and instrumental on what I have learned. I have been involved with the discovery or shown sources of placer many times ( no exaggerating ). You already know that there are many variables in the weathering / decomposition of gold. Distance to the source based soley on the courseness of the placer can be misleading based on several factors.

Things to consider are how long the gold bearing area of the vein has been exposed to the surface, composition of the host rock, and weathering. Topography plays a major roll as well, because it ties in with weathering. We dont know what the rainfall rate, lifting or elevation, and topography was at the original time the gold became exposed to oxygen. So , if the gold was eroded a thousand years ago or or a million, its actually possible that depending on the factors above, it could still be relatively close to the source or be miles away.

Weathering of your gold would suggest that the source of it is within a half mile perhaps. None of the gold looks all that course to me and it would appear that some rounding of the gold has taken place. The weathering of your gold my have been caused by gravels flowing over the stationary specimens, which could mean the source is near. However if the rainfall and weathering was heavy or commonplace when the gold was originally exposed, then it may have traveled a long way in a very short period of time, leaving very slighty rounded specimens like yours.....Your best bet is to sample upstream periodically, but I know you know this already.

Tortuga, purplish looking quartz is somewhat common in the some areas of the state , but it is not necessarily " amethyst".......Genuine Amethyst with gold would be very desirable, but exceedingly rare. If you have genuine amethyst with gold , please post it ...I`d love to see it.

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Tortuga, purplish looking quartz is somewhat common in the some areas of the state , but it is not necessarily " amethyst".......Genuine Amethyst with gold would be very desirable, but exceedingly rare. If you have genuine amethyst with gold , please post it ...I`d love to see it.

I always thought amethyst was just purple quartz because it isn't as hard as a gemstone like topaz or sapphire but I could be wrong.

My nugget is just a little .80 gram piece when viewed under a loupe has a tiny bit of dark reddish/purple quartz on it associated with nuggets originating from up on the Potato Patch. Nothing too crazy.

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They look a lot nicer now :)
Not that I know anything...but, I would be looking for that Iron dike :)
Tom H.

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One thing that wasn't mentioned is how close together those nuggets were found. If you have bonafide patch, or they all seem to be trending together it is unlikely that the source is too far away.

Nuggets don't usually move as a flock.

I do remember a story from a friend of mine in Australia. His wife went one way detecting and he went the other on quads. At the end of the day they each had a nice 1 ounce piece and the some bits and pieces. The wife said let me see that 1 ouncer you got. She put it together with her 1 ouncer and they fit together perfectly, indicating at one point they were the same 2 ounce nugget that had broken in half.

They went to his dig hole and took a GPS reading, then drove to her dig hole and took another GPS reading. The two matching piece were over 1 km apart from one another.

Doc

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I agree with Adam and will add a little. It seems most people believe that gold leaves the vein already exposed. Well maybe say a 1 gram nugget leaves the vein in a 3 inch diameter chunk of quartz. How far might that travel for how long before the quartz is eroded away leaving the nugget exposed without any or very little quartz left attached? In my humble opinion, the appearance of a nugget doesn't necessarily mean it has traveled a short distance or a long distance. Too many variables involved along with possibly many thousands of years of geological change.

I know a couple placer deposits that no source was or likely ever will be found. Some of the gold I have found at these placers appears well traveled and some doesn't appear disturbed.....smashed, rounded, or flattened.....at all. I myself believe gold can travel much farther than people realize and still be pristine. Also, just because a nugget is well rounded doesn't necessarily mean it has endured a long arduous journey. A well rounded nugget might have traveled a short distance in a rather violent way. Just my 2 cents worth of course. Dennis

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Geesh I could write a book on this subject alone. But generally Adam is correct. There are so many variables to consider, and based on the lack of these details in Rob's discription I would not venture a guess on those nuggets. :) AzNuggetBob

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OK Rob opened up a can of post-1452-0-02881700-1442221906_thumb.jp :P
But I think it is an important subject.
Here Is some of the things I look for or think about when I find a nugget.
things like was the gold shallow or deep, whats the average rainfall in that area,generally speaking, a lot of flash flooding etc?. what is the host rock in the nuggets, quartz,hematite,magnetite,other? was it found in a creek or on a hillside, what is the grade or slope of the ground, steep or flat, just some of those things that make it a lot easier to help determine the distance of the source. if your there it makes it a lot easier. and of course never base your opinion on one or two nuggets. three or four that's a different story. now the character of the gold is becoming more consistent and not just a fluke nugget(s). I hate those suckers they can really throw ya off. :spank::D
AzNuggetBob

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Here ya go all, a little info that may come in handy. :ph34r:

Doc
I found this topic on one of your threads I was reading awhile back, but cant find it again and my answer will fit here too, soooo
I think I know why your finding large gold below smaller gold on that spot. your not the only one running into this puzzling situation. even though I have little info on your spot this could be whats causing this. there is a good chance the gold is eroding out of a vein running along a canyon wall to the left or right of the wash your finding the nuggets in. this will cause the nuggets to erode out and travel down the bank into the wash in random order because they haven't been reclassified by size by the creek or wash your finding them in yet. this also could mean they haven't been in the creek you found them in for very long, so they are coming in very close by where your finding them. also if the wash is fairly flat left to right and the nuggets your finding are lining up more along one side of the wash than the other. (this can give you a clue what side canyon the nuggets are in coming from). hope this helps.

Finding semi-virgin patches 101
If the wash was hand stacked by the old timers working it, hike to the top of their stacking, up at the top they almost always stacked the rocks higher up on one side of the wash than the other.

here is why.
They knew what side of the wash the gold was coming in from and stacked the rocks on the opposite side, behind them as they worked up it.
put your back to the highest stacked rocks in the wash and look up, your probably looking at the source of the gold. and a possible hillside patch. :)
There is a good chance you'll find an exploratory test dig hole(s) from the old timers up on the hillside too, they may be covered by brush and hard to see from below.
Why didn't they dig up the hillside and run it? because the gold may have been too scattered out for hand digging and not concentrated like the wash. That's were a detector comes in handy.
AzNuggetBob

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Hey AzNuggetBob,

Great information. I have seen some washes with higher stacks on one side vs. the other. I might have to go back and investigate some of those locations as I never found the hillside gold (if any exists).

Looking forward to the cooler weather heading our way soon and hopefully some water in the major drainages for dredging.

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Interesting thoughts Bob.

What caught my attention was the heavy gold being lower down slope than the lighter.

We tend to think of it the other way round i.e. the heavies digging in and getting caught up slope nearer the source.

What do you recon.......?

1) reef or lode system was quite enriched with solid Au, but as time went buy and it was eroded deeper, the values decreased and started pinching out, hence lighter stuff last to be eroded.

2) the slope angle in eluvial/colluvial placer dictates the magnitude of gravitational force exerted on the mass of an object. i.e. Gentle slope = greater inertia of heavies to remain stationary, movement only from basement erosion. Steep slope = heavies inertia is maintained, once it starts to move it has the mass to keep on going. (Newton's first law of motion)

3) faulting or folding tilted the eroded placer. What was once the ridge to is now the gulch, the gulch is now the ridge top. This has other implications too, such as stream flow direction reversal etc., Since stream channels tend to follow faults or joints in the country rock, a prime hinge point for buckling.

4) level ledge on erosion slope, all the heavies due to their mass get trapped on the ledge, but lighter bits continue on down slope due to rivulet and eolian erosion. (this would leave smaller pieces above and below the heavies, and if the ledge were a gulch bench the lighter bits would enter the wash and be taken away)

Scratching the bottom of the barrel now. Anymore?

I missed the other post where you all discussed this.

I hope you find the mother lode there Rob!

Cheers

Kev.

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  • 2 weeks later...

Rob,

Do you have before and after photos of the nuggets? I am assuming nuggets don't always look like pretty yellow wedding rings gold when found?

How do you get the crud off? How do you even know its a nugget and not just a hotrock or piece of magnetite, which can be quite heavy too?

I have a 5 pound hunk of magnetite I got in a wash below an old gold lode mine sw of Payson years ago. It was solid black but stuck to a magnet.

We don't have nugget ground in the Midwest USA that I know of yet. Sure do envy you guys in Az, Ca, Nevada at times..

-Tom V.

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Hey Tom,

Here is one of the threads that show some of the nuggets still dirty. You will have to scan back a few pages on the forums to find the others.

http://forums.nuggethunting.com/index.php?/topic/11628-should-i-clean-them-i-hate-cleaning-gold-nuggets/

Most nuggets, are going to be dirty. Some might be just covered in dirt, others caliche or other material they have been sitting in for years (hundreds if not thousands). I have found bright, shiny nuggets on bedrock after Winter and Monsoon rains.

Anything that sounds off on my detector I will investigate. If it's an "unknown" I will take it home with me and investigate further. For the most part, rocks such as basalts/ironstones are pretty easy to ID and I just kick them out of the way. There is always a chance if you don't pick them up and examine, they could have some gold in them (ironstone at least).

Hope this helps a bit,

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