# Is a yellow solution from nitric a specific indication?



## Ragnor (May 29, 2017)

I conducted a test on a 1 gram ore sample today in a 25ml beaker using just enough 68%nitric to cover the sample and further diluted that solution with an equal volume of water. A nice slow dissolution (safety conscious). 

Again I get a yellow solution which turns to a rusty orange at higher concentrations. 

I have started doing some reading, but have not run across the answers yet as to what colors mean what metals. 

Is the yellow reaction specific to a certain metal? That last batch that started off like this did test positive for platinum (stannous test) after it was fully reacted.


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## 4metals (May 29, 2017)

Unfortunately simply color change rarely can pin down a specific metal, especially yellow.


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## Ragnor (May 29, 2017)

Thank you for the response. 


I'm going to add this image. Can anyone confirm that this is a positive result for platinum using stannous test? 
This is the result from the solution I made made today. I have not yet added any hcl or salt.

Also I was wrong, it's a 50ml beaker


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## g_axelsson (May 29, 2017)

Check this thread.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=41&t=5271&p=45030#p45030

Göran


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## Lino1406 (May 29, 2017)

Platinum will not dissolve in nitric acid


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## Platdigger (May 29, 2017)

Except, with enough silver.


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## Ragnor (May 29, 2017)

Ag, Au, Pt is a very high probability for this material.




"I don't know Herman, that looks like pyrite to me", I said. "That's the gold!" the old man snapped back at me angrily.....


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## Ragnor (May 30, 2017)

This is the result after adding 1/4 tsp. of table salt to the mix.


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