Should I purify/refine 925 silver for silver nitrate?

I've read all the threads and precautions on making silver nitrate but the cost here in Israel is just too high to buy it (300$ for 100g or 200$ for 50g of silver nitrate for pure 99+% grade). There is nitric acid in our studio (for etching) and 925 silver (sterling?) can be easily obtained. A few questions before I begin:

1. Can the nitric acid be warmed with bain-marie to haste the process instead of using a hot plate? This will be performed outside so having electricity can be a problem.

2. Is 92.5% of silver nitrate enough for various alternative processes (collodion/salt paper/...) or should it be refined? I'm not planing on manufacturing Kodak grade products, just experimenting with old photographic processes.

3. If it does need to be refined, what is the best/easiest way? Copper wire?

4. On perfect conditions, one should use 75g of silver per 100ml of nitric acid to convert all the acid to H2O and NO (which converts to NO2 with air?). This should yield about 1.57g of silver nitrate per 1g of silver. Does refining silver yields a much lower values or roughly the same as pure silver in the solution?


Thanks,
Omer

Hello Omer,

I tried to find you a cheap supplier and researched the APUG archive. I think you can buy %60 cheaper at USA and they send it worldwide. But I dont know that thread goes back before metal prices went crazy. Check the suppliers , Bostick Sullivan is a good place to look for. I dont know 100 grams of silver nitrate costs you at DIY process. May be You can tell us.

Please find herebelow the copy of old thread.

AnselAdamsX

03-22-2012, 07:29 PM see the Formulary has 100g for about $300. I also see an eBay seller has 100g for $100. Anybody buying from the bay? What quantity/price do you normally buy?

Vaughn

03-22-2012, 09:16 PM

I get mine from Bostick and Sullivan. High quality, consistent quality, and dependable friendly people to deal with.

100 grams to 200gm of Silver nitrate is $1.29/gram (At $129 for 100 grams, that is less than half of PF's prices). 200gm to 500gm is $1.17/gram. Over 500gm is $1.10/gram.

I usually buy it 30 grams for $39 -- no extra shipping charges at this amount. Tho there was no extra charge when I last bought 50 grams from them.

Vaughn

kb3lms

03-22-2012, 09:20 PM

Check out Salt Lake Metals and Artcraft chemicals. Last time I checked, I think Artcraft was a bit cheaper.

Artcraft's website currently says $112.75 for 100 grams.

htmlguru4242

09-18-2012, 05:26 AM

Just paid $39 for 30 grams from Artcraft.

Umut

Hello Umut,

Forgot to mention it is not possible to order silver nitrate from abroad. The customs office allows only authorized labs to import such chemicals.

Thanks,
Omer

By the way I checked the web and learned 100 grams of Sterling Silver costs 125 dollars. I dont know the price of nitric acid but it gives you an alloy with %7.5 copper.

Buying purified silver nitrate costs you same price. Try to buy 30 grams at the start from Bostick Sullivan and you will be happy.

Umut

Omer,

Sorry to hear that, may be you can obtain from an university lab or tell your problem to an private lab to get the chemicals from outside. I think sellers are skinning the cat there. May be even buying these chemicals from a supplier as an individual person would be difficult also.

Bad luck really.

Best wishes,
Umut

My school allows me to use their lab permission to order chemicals locally. No luck trying to get chemicals from outside...

Actually I already have about 200g of 925 silver so with addition of nitric acid the school supplies it costs me nothing (but my health...) to synthesize silver nitrate.


Omer

Omer ,

I searched the web and I learned its EXTREMELLY dangerous. I advise you as your friend to sell your 200 grams of 925 silver , put some money on it and buy from local supplier. People buys 30 grams , may be you can try that amount to buy for start.
Fumes kill you or not , not another option. Alternative Processes are expensive and may be you can try another process.

Take care,

Umut

I've made my own silver nitrate with 99.9% pure silver, it's not a very difficult process and not that dangerous if you know what you are doing. First of all it's important to do it outside or in a fume hood. Second, wear protective glasses and gloves at all times when handling the chemicals. You don't need a bain-marie for heating up, a small bunsen burner or heating plate will do, just make sure you use a large enough beaker that is heat resistant because once the reaction starts it's exothermic and it gets really hot. You can use .925 silver but you will have contamination of Copper Nitrate (blue color), since copper nitrate does not crystallize easily you just have to wash your silver nitrate crystals a bit more till you got rid of the blue color and your fine. Don't store the crystals in anything plastic!! only use glass containers, otherwise you will be left with a gooey substance after a while.

I will be using Pyrex flask for the process and brown glass containers to hold the crystals. Is this OK?

How should I wash the crystals? Silver Nitrate is soluble in water, if I wash with water, wouldn't it dissolve the silver crystals too?

You have to wash with Nitric Acid, not with water otherwise you will end up with no crystals. Just put your crystals in a coffee filter and use a funnel to pour Nitric Acid on it to get rid of the blue Copper Nitrate contamination. Pyrex should be more than fine and the brown glass is certainly OK for Silver Nitrate.

Buy an chemical mask if you dont want to kill yourself. You can import an mask as least. Which mask protects from fumes of this process ?

The best thing is just to do it outside, let the reaction begin and then take enough distance. You could wear a gasmask but why should you? Once the reaction is running there is nothing you can or should do, there is no reason to be in the vicinity of the fumes.