# Testing silver nitrate



## Cwcoon5 (Mar 16, 2017)

First of all I would like to say thank you to everyone that has dedicated time and information to this forum.
The process of precipitating silver with copper I have done many times and the outcome is always differently.

Is there a way to test the silver nitrate before and adjust the solution for ideal conditions to precipitate silver?

Thank you in advance.


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## FrugalRefiner (Mar 16, 2017)

Cwcoon5 said:


> Is there a way to test the silver nitrate before and adjust the solution for ideal conditions to precipitate silver?


What do you want to test it for, and what do you want to adjust?

A quick test to see if you have silver nitrate is to take a drop of it and add a drop of HCl or a grain or two of salt. If there's silver in solution, you'll see a cheesy, white precipitate.

If you want to know the silver concentration, you can use a Volhard titration.

When I need to dissolve silver, I use the smallest amount of nitric needed to dissolve the silver. I add distilled water to double the volume. Add copper.

Dave


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## 4metals (Mar 17, 2017)

How does the silver come out differently? Different appearance? Different texture? Different purity? We need more details of how you digest, what you digest, how much nitric you use, and how you determine all of the silver is out. Then we can likely assist you in getting to consistency.


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## Cwcoon5 (Mar 24, 2017)

I process sterling silver with Hno3. Usually 10 ounces Sterling cleaned and melted and dissolve in 300ml Hno3 68% and 300ml dh2o warm until reaction stops. Making sure I always have silver undissolved in solution. With these numbers I know pretty close how much pure silver I have in solution with copper as well. After this process I would like to be able to test and or adjust the silver/copper nitrate solution for the best parameters before precipitating with copper. Sometimes when I precipitate and grows a hard crust of silver on the copper or it falls off quickly and produces gas nox or sometimes doesn't precipitate. And sometimes the last precipitate is much darker in color towards the end of process. therefore I'd like to test or adjust before precipitating to get a more consistent outcome. I'm also working on a process to recover 50% of the hno3 during the dissolving process. And when I try different apparatus and different configurations and pressures during dissolving process I may end up with a hno3 silver/ copper solution with higher or lower concentrations of silver/copper/dh2o/hn03/contaminants. Therefore I would like to test and or adjust the solution before precipitating. Thanks again and I hope this clarifies some of the questions.
KADRIVER has seen my process and I have purchased LAZERSTEVE video silver A to Z.


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## Topher_osAUrus (Mar 24, 2017)

The darker cementing at the end is pgm's displacing after the silver is finished, or close to.

The differences in the cement quality you are experiencing (most likely) is due to subtle pH differences, as well as dilution. I can only conjure up that guess though, and don't have any scientific proof of that theory. 

Kurtak has one (or a few) really good posts on cementing silver.
:arrow: http://goldrefiningforum.com/phpBB3/viewtopic.php?f=37&t=23441&p=246984&hilit=dilute#p246984
This is one of them.

I like to cement until it starts to looks darker (the cement) or slows down significantly. Start to clean that cement up, putting the first rinse back in the silver/copper nitrate solution. The subsequent washes, I save separately (I'll get to that).

The rest of the solution, I let the darker silver and pgm's cement for a few days, stirring it a couple times daily. After it tests negative for values, I start to clean up that cemented material. Using the saved washes from the cleaner looking silver cement. Then, that final wash, I always use that as the starting water in my next nitric dissolve of silver material. It helps cut down on waste (and is in your best interest) to reuse as much as possible.

May I ask, what you are using/doing to save on the nitric consumption?


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## Cwcoon5 (Mar 26, 2017)

Yes I've read that article about 3 mistakes for beginners and that is correct. I went back to that article several times.
What should the pH be before precipitating. I'm getting roughly a 2 or 3 pH..
And to recover some of the hno3 I'm capturing and refluxing the nox. And passing it through H202 and h20.
And your phrase.
I fix whats broken. I reuse whats "trash". I do what i can. I live by.


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