Gold from decomposing granitic rock

Boarteats

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Have a buddy who has some boulders of decomposing gabbro in his yard. I happened to notice a fair amount of iron oxides in a couple chunks, so offered to crush them up and pan for any gold. See attached pic for results. Shiny bits appear to be gold but haven't done a stannous test yet to be certain. However, pretty confident that it's gold. The pan below was the result of crushing up a couple of fist sized rocks and quick (not careful) panning.

I have very little experience with this whole gold prospecting business, so would like to solicit some experience based opinions. On a scale of 1 to 10 where 1 is trivial amount of gold and 10 is 'lie to friend and try to haul away his boulders in the dead of night', how would you rate the potential for gold yield? (Just kidding about stealing rocks but you get the idea) :)
 

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smokeythecat

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Yes more than likely it is. Gold occurs in Frederick, Carroll , Washington BALTIMORE, Hartford and Cecil counties. And at my house.
 

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Boarteats

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Yes more than likely it is. Gold occurs in Frederick, Carroll , Washington BALTIMORE, Hartford and Cecil counties. And at my house.

You ain't kidding brother. Found gold in my yard quite by accident several months back. Now, I've started looking around for more. Will be attend my first central Maryland GPAA meeting tonight.
 

AllenJ

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Sounds like somebody has the fever! It's amazing at how little gold in a pan it takes to give it to you, my first pan was less than that and now I go every chance I get. I hope you have a great time at your meeting.

I'd offer my "experience based opinion" but I don't feel qualified since I've only been doing this for about 5 months now.
 

smokeythecat

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I'm not sure I'm doing the creek this year. We have a "cougar" hazard in the area.
 

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Boarteats

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Sounds like somebody has the fever! It's amazing at how little gold in a pan it takes to give it to you, my first pan was less than that and now I go every chance I get. I hope you have a great time at your meeting.

I'd offer my "experience based opinion" but I don't feel qualified since I've only been doing this for about 5 months now.

True, true. Gold prospecting is my latest obsession. Something very primally satisfying about it.
 

bug

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looks like pyrite sulfides. smack em with a hammer and watch if it crushes to powder.
 

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Boarteats

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looks like pyrite sulfides. smack em with a hammer and watch if it crushes to powder.

I've been fooled by pyrite many times, so I never assume gold. I prove it before believing. Parent rock samples had strong positive result for gold with stannous chloride test. Moreover, I took a torch to this sample to fuse the very fine gold into bigger pieces, so it'd be easier to see. That is certainly not pyrite.
 

bug

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Does it flatten out or crumble to powder when you smack it? That basic test will reveal the malleability of a metal- lead, gold, copper...
 

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Boarteats

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Does it flatten out or crumble to powder when you smack it? That basic test will reveal the malleability of a metal- lead, gold, copper...

It's gold, bug! My friend, Stan Chloride, agrees with me.
 

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Boarteats

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I hope its gold.

But judging from what I have read, stannuos chloride is for testing for metals in solution. I have not found anything on testing solids with SnCl. What method did you use exactly?


Maybe having no solution is a problem. :tongue3:

Ok, now ya’ll are just trolling, but ill give you style points for the bad pun.

Of course, I dissolved samples in AR for the SCl testing. Oye vey.
 

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Boarteats

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Rocks in AR? Did you pulverize and pan the sample first?

This is getting interesting. Way outside of my experience. Let us know how it works out. Stay safe.

Caveat: this is a summary, not a how-to. I’m leaving steps out. Do not try this at home or elsewhere.


Yeah, have to crush ore samples to approx 100 mesh and roast (if sulfide might be present). If testing for gold, just add AR and stir. If testing for PGMs, will need to warm AR. Depending on sample, panning down to heavies might be advisable. Was not necessary in this particular case. After adequate time in AR, filter out solids. At this point, SnCl testing is possible. Can always be complications but they generally result in false negatives instead of false positives.

Lots of caution is required when working with AR! I use respirator, goggles, gloves, smock, and lots of ventilation. I also keep a bucket of water+baking soda near by. Saved my butt just last week. Had a flask of AR slip out of my gloved hand. Dropped on my work bench. Acid flew everywhere.
 

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mendoAu

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Now that's just too dang funny....a sissy little cat (Cougar) chased me off my claim. Get a darn dog.:

DSC09104.JPG
 

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