# What is This...Grey powder



## jeneje (Feb 23, 2013)

I have been processing some silver i had in HNO3, after disolution i have this silver/grey powder that want go into solution. Any idea what this is. 

Thanks
Ken


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## butcher (Feb 23, 2013)

Is This home made HNO3?
What is the source of silver?
We need details or a few clues.


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## jeneje (Feb 23, 2013)

Sorry for no details,
The feed stock was 925 steriling and the HNO3 is teck grade. Nothing different here, just regular silver as far as i know.

Ken


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## tek4g63 (Feb 23, 2013)

Did you use distilled water to dilute the nitric, or tap water?


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## jeneje (Feb 23, 2013)

tek4g63 said:


> Did you use distilled water to dilute the nitric, or tap water?


Yeah Thad i diluted the HNO3 with tap water trying to slow the NOx down when i first started. Does this make a difference?
Ken


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## tek4g63 (Feb 23, 2013)

Yes it can. Tap water has chlorine and other chemicals and minerals in it. Some times these can cause some of the silver to precipitate out as silver chloride. 

I've personally never seen quite that much produced from tap water, but just remember that with silver it is always best to use distilled water.

But I could be way off on the cause of the sediment. So you may want to wait for butcher or someone else to chime in before taking action.

Thad.


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## jeneje (Feb 23, 2013)

tek4g63 said:


> Yes it can. Tap water has chlorine and other chemicals and minerals in it. Some times these can cause some of the silver to precipitate out as silver chloride.
> 
> I've personally never seen quite that much produced from tap water, but just remember that with silver it is always best to use distilled water.
> 
> ...


Thanks Thad, that would seem right because of the color. I knew to use distill water...No excuse for not using it, just did not think, got in a hurry. If its not one thing - its two here lately.
Thanks again.
Ken


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## Palladium (Feb 23, 2013)

Have you incinerated it to see if it would go into solution then?


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## philddreamer (Feb 23, 2013)

From looking at the pic, the color resembles AgCl exposed to light.
Rememeber, when digesting silver in 50/50 nitric/water it MUST be distilled water, otherwise the chorine that's present in the tap water WILL precipitate some silver; as you know, the AgCl now won't dissolve. 
Phil


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## philddreamer (Feb 23, 2013)

Ralph, instead of incinerating, shouldn't he first try to convert to elemental silver a small sample with a bit of lye?
Phil


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## Palladium (Feb 23, 2013)

Rotfl!

Your right brother. For some reason when i read the post i was thinking it was silver that had been used for inquarting and this was what was left over. I figured the residues would have been au, pd, pt..... Now i see it was sterling. :mrgreen:


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## Palladium (Feb 23, 2013)

You could try dissolving a sample in excess ammonium and adding cl in some form to verify it is silver chloride first.


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## jeneje (Feb 23, 2013)

First - thanks guys for the help here. Lately my mind has been on other things, really i should'nt even be doing it...but i have to move along with this for personal reasons. 

If i understand what you guys are saying, dissolve a sample in ammonium and add cl to it for a positive Ag test. If the test is positive use lye to reduce the Ag chloride to silver. When mixing the NaOH should i use distill water for this? If this does not work dry and incinerate.

Thanks
Ken


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## philddreamer (Feb 23, 2013)

" ...dissolve a sample in ammonium and add cl to it for a positive Ag test."
If you suspected PGM's, like Palladium suggested, you would dissolve a sample in ammonium, but, you mentioned that you used tap water when dissolving, so it means that you most likely have AgCl.
Just take a small sample and add a bit of lye, and watch its reaction, (it will turn black, elemental silver, if it's AgCl). If it doesn't turn black or dark brown, then do the ammonium test. You can use tap water when converting with lye, (sodium hydroxide.) 
If you are cementing, use distilled water; but if you're going to drop the silver with salt or HCl as AgCl, you can use tap water. (When you have AgCl, do not dry nor incinerate!)
Phil


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## jeneje (Feb 23, 2013)

philddreamer said:


> " ...dissolve a sample in ammonium and add cl to it for a positive Ag test."
> If you suspected PGM's, like Palladium suggested, you would dissolve a sample in ammonium, but, you mentioned that you used tap water when dissolving, so it means that you most likely have AgCl.
> Just take a small sample and add a bit of lye, and watch its reaction, (it will turn black, elemental silver, if it's AgCl). If it doesn't turn black or dark brown, then do the ammonium test. You can use tap water when converting with lye, (sodium hydroxide.)
> If you are cementing, use distilled water; but if you're going to drop the silver with salt or HCl as AgCl, you can use tap water. (When you have AgCl, do not dry nor incinerate!)
> Phil



Phil, you are correct, addition of lye does reduce it to a brown precipitant in the test tube. I always learn something new here. 
Thank you Phil,
Ken


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## philddreamer (Feb 23, 2013)

You're welcom, Ken!
If you add a bit of sugar, it will turn into silver metal.
But, be aware if you haven't done the lye and sugar conversion before... it will get hotter than a pistol!!!
Phil


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## jeneje (Feb 23, 2013)

philddreamer said:


> You're welcom, Ken!
> If you add a bit of sugar, it will turn into silver metal.
> But, be aware if you haven't done the lye and sugar conversion before... it will get hotter than a pistol!!!
> Phil


Thanks Phil,
I have never done the lye and sugar, this will be a first for me. I will reasearch this procedure. It should be fun to watch the silver form. Are there anyway to control the heat? 
Ken


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## philddreamer (Feb 23, 2013)

> Are there anyway to control the heat?


Ken, by all means, do some research first! Follow all the safety procedures for handling lye, (sodium hydroxide).
Add the lye first, in increments; after all the AgCl has converted into Ag oxide, start adding the sugar, also in increments. If you add it all in one shot, you'll have a volcano!

Another process for converting AgCl into metalic silver is diluted sulphuric acid and placing a piece of aluminum metal. But, first things first!
Take care!
Phil


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## tek4g63 (Feb 24, 2013)

Ken,
As Phil mentioned, once your ready, be very careful and go slow with this process. My first time I only did a tiny amount and because I didn't fully understand how violent and hot this reaction gets, it ended in a mess. I took appropriate measures to ensure safety in the event something went wrong and I'm very happy that I did. 

I made many mistakes, first was I use a glass vessel, test tube, second was I tried going too fast, but my biggest mistake was underestimating the reaction thinking that because it was such a tiny test " what's the worst that could happen". It was a fast foamy boil over then breaking glass all of which made a mess in my catch basin that had to be dealt with. What scared me most was the thought of how much worse it could be if someone made my mistakes on a larger batch without proper fail safes in place. 

You probably already know this but, be careful all the time. NAoH can and will burn you as bad as any of the acids we use. Fortunately I have never experienced it first hand, but several people I work with have scars to prove it. Where I work we get NAOH in in 50 gallon drums, along with many other caustic agents. Sometimes an operator gets in a hurry or careless thinking " it's not one of the acids, and my gloves are way over there, it will be fine" WRONG! We get 70% sulfuric acid, 70% nitric acid, 25% hydrochloric acid and many other acids in in 50 gallon drums and the funny part is in 20 years there has only been 2 acid injury's reported. There has been over 20 accidents reported due to NAOH or some other caustic solution. Just wanted to share that with everyone. I hope that everyone protects themselves and always prepares for the worst no matter how familiar you are with any chemical or process.


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## nickvc (Feb 24, 2013)

As an aside I like, I think it was 4metals that described this method, the idea of using tap water and adding a small amount of silver nitrate to it stirring and then filtering to produce water safe to use in silver refining and recovery as the chlorine has been used up already converting the silver nitrate to silver chlorides. Cheap and easy and ideal for those times you don't have any distilled water or the stores are shut or too far away.


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## Bushka (Feb 24, 2013)

tek4g63 said:


> the funny part is in 20 years there has only been 2 acid injury's reported. There has been over 20 accidents reported due to NAOH or some other caustic solution.



I'd like to add something to this. Caustic burns are much worse for you than acid burns. Acid burns tend to burn more at the surface, destroying the skin mostly. Caustic burns tend to soak into and through the skin, causing deeper burns below the skin layer.

I processed my AgCl with caustic and Karo syrup. Heat wasn't a problem for me as I was doing smallish batches. All of the initial heat generated is caused by dissolving the caustic pellets in water. You can minimize overheating problems by dissolving the pellets and then allowing the solution to cool down before adding to the AgCl. I don't know how much difference this makes as I've never tried it that way, but I do know that the solution gets hot even before the AgCl reaction takes place due to the "heat of solution" of the pellets.

Dan


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## Geo (Feb 24, 2013)

lye is (or was) a common household chemical used to make homemade soap.it was more accessible than most acids.caustic soda gives a false sense of security in that you can touch a solution with your bare hand with little or no effect at first. after a few minutes, you can tell your skin is getting slick.after about five minutes, it start tingling and itching on the sensitive back part of your hand and in the crease's where your hand meets your wrist and between the fingers.at this point, the damage isnt severe but is reaching the Dermis, having dissolved the Epidermis.if not removed and the alkali neutralized at this point, the Hypodermis will be breached. after this point is reached, scarring will occur. of coarse this is with a cold solution. when heated, all of this happens at a much faster pace.


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## Auful (Feb 24, 2013)

Lye (NaOH or KOH) does the same thing to your fingers, hands, cells membranes, lipids as it does to fat: saponifies them; turns them to soap! Lipids are almost as ubiquitous in the human body as proteins, so be careful!


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