# Microscope pictures of gold precipitate



## gobot (Sep 9, 2012)

I hear about this gold precipitate that is brown or even black. I would really love to see a 100x microscope photo of this type of gold if anyone has some pictures to share. I spent a considerable amount of time searching the internet for such photos but not really much out there when it comes to that. I'm really interested in the black gold type that is recovered from dissolving silver or mercury with gold.


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## butcher (Sep 9, 2012)

There are many photos of gold precipitate on the forum, in mercury it would look like a dirty lumpy ball of mercury.

The color of powder I like seeing are the light brown after using Harold's washing procedure (getting gold pure and shiny). 

Then the pictures of those beautiful melted buttons, or pretty pictures like Harold's bowl of gold corn flakes.


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## gobot (Sep 9, 2012)

Im looking for pictures of gold from mercury after the mercury was dissolved and not while it was still an amalgam. I have heard the gold looks like a black powder. Same with silver. Curious to see what that black powder looks like under magnification. The pure gold powder that appears brown to the naked eye I am very interested in seeing a 100x microscope picture of also while it is still in powder form. Just curious to see it I guess.


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## NobleMetalWorks (Sep 9, 2012)

When gold precipitant is black, like after stripping with a sulfuric cell, it's because it's finely divided. I am not sure about Mercury, but I personally wouldn't mess around with it, far too toxic. That's not to say the acids we use are not dangerous, but there are easier and better methods than Mercury.

If I remember next time I precipitate Au, I'll take a few pictures, I have a 100x digital microscope I can snap pictures/video with.

Scott


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## Geo (Sep 10, 2012)

in my younger( and stupider) days, i have used mercury to collect flour gold from concentrates and have both heated the mercury to evaporate it away from the gold and digest it in nitric acid. never has the gold been black in either processes. on the contrary, when gold is absorbed into mercury, it gets a type of cleaning that is different from any other solvent. the gold always came out looking like clean fine gold dust. normally, when gold precipitates out of solution black, its due to impurities coming out with it due to "drag down". clean gold precipitate will always be a light tan.any darker than that means that the gold is not pure. there are exceptions, such as colloidal gold which can range from purple to red. but for all practical purposes, pure gold will precipitate with a light tan color.


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## gobot (Sep 10, 2012)

I was basing my research from the web sight "prospectors paradise". On that web sight it said that the gold that falls away from the mercury after dissolving the mercury will be in the form of a black powder. I have no experience with mercury so this is not my observation but what I did read. There is alot of false information out there and that makes it hard on people like myself trying to understand gold recovery/refining. This is why I am glad I have found this forum. It is my understanding that this "prospectors paradise" information about mercury is based on the web sight "basement chemistry for the prospector". Please bear with me if my questions sound dumb because all I can do is research material and ask about what I have read.


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## gobot (Sep 10, 2012)

I guess it depends on the mesh/micron size of the gold as to which color it will look when recovered from dissolved mercury? Again, sorry if this is a dumb question.


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## Geo (Sep 10, 2012)

gold in nature (free standing gold) that is gold that is in metallic form and is free from the rock matrix, should be gold colored. only if it gets coated with something else will it appear black. gold that has been amalgamated with mercury, and the mercury is evaporated away from the gold, is bonded with other pieces of gold it touches. in other words, the gold dust will be stuck together to form one mass, like concrete.on the other hand, if you digest the mercury in nitric acid (WARNING: mercury is toxic and digesting mercury with acid releases mercury fumes into the air) the gold dust will be loose and in single particulates.


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