monovalent gold

[hodhod1403]

Nothing here looks like Gold.
If there is any Precious Metals in there you can put in a piece of Copper and they will cement out.
Just make sure it is acidic

I put a copper foil in the acid solution that contains gold(|) . After 24 hours, the solution turned black and the copper is dissolving and black particles have settled under it. Question? Why do you think the solution turned black and how long does it take to dilute it?

 

[Yggdrasil]

I put a copper foil in the acid solution that contains gold(|) . After 24 hours, the solution turned black and the copper is dissolving and black particles have settled under it. Question? Why do you think the solution turned black and how long does it take to dilute it?

I can't say why the solution turned black.
But the black particles may or may not be Gold.
Have you had a proper stannous test yet?

 

[4metals]

As @tmj883 pointed out there are deposits of Carlin type gold in Iran and you can find an excellent description HERE. There are some interesting and concerning points in the article, first and foremost the gold is contained in arsenic rich pyrite. In case the OP was not aware arsenic when put into acids, (hydrochloric, nitric, and sulfuric) produces a TOXIC arsine gas.

For your own safety stop putting these samples into acid!

Second the article mentions this type of deposit typically runs 0.20 to 0.25 ounces of gold per ton. At these concentrations you are looking to detect by crude analytics, gold in the range of 3.5 milligrams per pound of sample. Not likely to succeed.

So while it is likely true, the geology of the region we ASSUME the OP is in may contain gold in quantities that, as Deano said, are difficult to recover. Recovering gold from these deposits will require a lot of financial investment from larger corporations experienced working these type deposits.

More important @hodhod1403 consider the consequences of putting arsenic in acid!

 

[Barstool miner]

Well this an opinion I respect from Deano from down under. No stranger to gold in it's natural form.

Many times in my career I have been sent samples of ore that were not assayable by standard methods, either qualitatively or quantitatively. Yet the owner was convinced there was payable gold in the ore. None of them ever would own up to how they determined that this mystery material contained gold.


Best we can tell you from what you have told us is to screen the soil through a 5 micron screen with the hope the fine monovalent gold passes through the screen with some of the fines in the soil. This sample, having passed the screen may be separable by density in a gold pan enough to give you a sample to test further.


Still open to answers from other regions of the world about gold found in unlikely places.

Has anyone else here Washed a quantity of riverbed sand in a gold-bearing Area? Then, separate the water from the sand and put it in a clean Beaker. Let this water settle for a few days. Then, Use a Green Laser pointer to direct the laser light through the water in the Beaker from one side. What can be observed
suspended in the water should be nanoparticles of metals. Please do not Inquire, do!

 

[4metals]

What can be observed
suspended in the water should be nanoparticles of metals.

While seeing is believing, and I have no doubt about what you say, recovery as in concentration and separation, is the real issue.

 

[Yggdrasil]

Has anyone else here Washed a quantity of riverbed sand in a gold-bearing Area? Then, separate the water from the sand and put it in a clean Beaker. Let this water settle for a few days. Then, Use a Green Laser pointer to direct the laser light through the water in the Beaker from one side. What can be observed
suspended in the water should be nanoparticles of metals. Please do not Inquire, do!

What you see is particles of any valor from micro to nano size.
Quartz, granite, metals, oxides and what not in a sufficent small size to not settle completely.
The lazer just illuminate something.
The likelyhood of it to be a precious metal is less than any of the other lighter elements.
Both due to rarity and density.