Refining Sterling Silver Into .99 - .999 Fine Silver (minus silver cell) 

Thank you very much for the feedback! It's all fun to do isn't it!? And it can be a little profitable on top of it!

Extremely entertaining. I’ve borderline gotten addicted 🤣 I scarf up sterling every chance I get now. Just keep telling myself it’s an investment lol.

Thank you! I have a number of smelting videos if you didn't see them already! 👍

Thank you very much!

Use a good quality sand or Petrobond to make your mold 👍

Thank you! I got lucky finding the fume hood locally at a good price, and found most of the glassware at good prices on Amazon.

Thank you!

Yes - quite remarkable - which is why both of us remarked on it.

@@six-gun indeed

Copper nitrate is a beautiful blue color. Copper chemistry in general has great colors.

@chemistryofquestionablequa6252 agree!

Thank you!

Thank you! Yes I sell a lot on FB.

Thank you very much!! Sorry I just got the RU-vid analytics app and now seeing so many comments I never knew I had ☹️.

How much water to nitric acid would you use ?

It's not real difficult.... Just make sure you get good nitric acid.

Hi, yes I did dilute the silver nitrate with distilled water prior to inserting the copper.

😆 that's dedication!

Pretty much any inexpensive filtration pump should work. I got a pretty cheap one from Amazon. Here is the one I got, but I'm not sure it's available anymore: Filtr8 Lab Filtration Pump

@@JoshuaAndersonLife Thanks, that helps a lot!

The nitric acid I buy is 70% concentrate. During the refining process when I dilute it I always dilute 50% nitric acid with 50% distilled water. At times to speed up the reaction more quickly I will add the 70% nitric acid without any additional dilution.

Sorry, I'll come to answer a question and see questions I had missed so long ago. To be honest, I am not entirely sure how long these carbon filters last, and I could not find any solid information on this particular model. I have only done a few full refining processes with my current filter. But they are pretty heavy duty, weigh about 45 lb, and are over 6 inches thick. Considering the nitric dioxide is pretty toxic I probably would not want to do more than about 10 refining processes with one filter.

On my particular burner it was set in the middle at 3 (out of 6), and it's turned off during the process when the copper is inserted and the silver cement is forming, I just happen to have it sitting on there. During the drying of the silver cement it can be set at a temperature of your choice, usually I just like it so that it does not bubble when there's still a fair amount of moisture in it. Sorry I just got the RU-vid analytics app and now seeing so many comments I never knew I had ☹️.

You can skip the zinc and just use iron, a lot less expensive. I find rebar works well.

Cool thanks that's what I was wondering...

So what would u say purity is

He said that sterling s. is .925 which was the first red flag

@@trollmcclure1884 ?? Sterling silver is also called 925 and is 92.5% pure and when refined it become much more pure but without a silver cell it doesn't get to 999 so I'm curious what it average is comin outta the nitric solution

Not likely enough for it to make any significant difference. To further refine from this point you would really want to use a silver cell.

Thank you! I have actually made a video of making shot, but I never did post it. I'll have to look at doing that again.

Joshua Anderson oh cool man that’s awesome! Good thing you shared your channel link in the silver groups on FB or I wouldn’t have seen these cool videos. I could watch videos like this all day long 😂

Thanks man, I really appreciate that!!

the copper nitrate can be retrieved by simply tossing iron in like the copper for silver. Noble metals don't follow the hierarchy that base metals do, so in sequence you could retrieve any and all metals separately down to the lowest (though iron is the cheapest to sacrifice). however if you do this, your acids are toast... because your solution can be refreshed over and over or simply reused many times after taking the noble metals. but yeah iron would be a cheaper loss in doing that. In smelting you can retrieve copper as well with potassium chlorides i do believe from the slag. I don't reccomend smelting silver chloride either like he did, turn it back to a oxide first for highest yield, silver can volatize off with the chlorides. oh an be sure to use some borax on your ceramic melt dish otherwise it will absorb into the dish (man i screwed up big there once). Definitely cover your noble metals with borax! I usually mix the silver oxide with the borax pre-hand as it covers the silver preventing volatizing off under the high heat torches i use (i melt tungsten at times)

I don't believe there's really much of a way to recover any of the copper in this process as it's ions are virtually used up to create the silver cement.

Hi, I was able to buy this fume hood from somebody locally, but you can buy them online and they start at around $1,000.

I found the fume hood on a local sales post. Most everything else I bought off of Amazon.

Yes, that's copper nitrate. I don't bother trying to extract anything from it, and just take it to my local hazardous waste disposal facility.

I melt it in a furnace first and pour usually into shot.

@@JoshuaAndersonLife thank you, I’ve got it down pretty good now, then I run the shot through my silver cell and make crystals

I have over 70 ounces of sterling silver would love some more knowledge on this.

Yes I started off with nitric acid diluted with distilled water 1:1, that's what's used most of the time. However, once you get used to the reaction you'll start using more 100% nitric acid, this will also prevent using too much liquid in general as well.

I should add, I also use/buy highly concentrated ~70% nitric acid.

2oz seems like a lot to lose. Maybe the cement isn't dry enough and still has some moisture/water weight to it?

Yes, the Lego minifig and the lion head pour videos are both using the refined silver from the video.

Nice! No I haven't but I'm interested in it. Do you do both? Do you pour as well?

Yeah im also curious about questions b and c. Could you maybe do a video on the final filter?

A) I always either use 100% nitric acid or 50% diluted. If there's little reaction happening, I'll likely add 100%. If I'm just keeping an active reaction going I'll add 50%. When adding 100% just add smaller amounts until you get your desired reaction. B) Yes, I do reuse the copper wire from prior refining processes. But, I like to start each one with new copper and then add the used copper about half or ¾ the way through. C) I used the same vacuum filter and about 2½ - 3 gallons of distilled water, then switch to tap water.

@@JoshuaAndersonLife do you lose much with this method? I heard a lot of different methods but not many people discuss yield.

@@SoSo-li6dn • Total yield = 873.4 g (28.08 oz.) • Starting Sterling Silver = 971 g • % Fine Silver .999 refined from the Sterling Silver = 89.948%

@@JoshuaAndersonLife thanks sorry, I did watch until the end - so sterling is £7.75 impure so the total loss is only 2.5% contaminating your copper sulphate? Pretty good when you consider that the scrap man pays about 80% of the spot price for sterling, and 88% for pure - and thats only if you have over 5kg - They say they buy bars at 100% but im assuming they would only accept certified stuff.

Thank you! Yes they are carbon filters. I've only done 3 processes of silver refining so it hasn't gotten that much use. I bought the fume hood with a new filter but the seller didn't know how long they last and at the time I didn't find much good info online either.

@@JoshuaAndersonLife Ok great I appreciate. Looking into fume hoods now but you are right I'm not finding great info on this. Keep up the great videos!

@MN11197 If you do find anything out please pass along the info. Thank you! 👍

@@JoshuaAndersonLife Will do.

Decided to try chat GPT and here's what it told me: Carbon filters in fume hoods typically need to be replaced every 1 to 3 years, depending on the type of chemicals they are filtering, the frequency of hood use, and the concentration of fumes.

Not exactly... There's not enough silver plating to make it worth it.

Sorry I just got the RU-vid analytics app and now seeing so many comments I never knew I had ☹️. Sounds like you probably came out fine you just needed to rinse thoroughly with distilled water.

If you go too far, the copper wire will begin to fall apart and you'll have copper "splinters" in the silver sponge. It can be a real pain to find and remove all of it. If you use wire, use very thick wire and keep a close eye on it so you can remove it before it contaminates your batch. A lot of people prefer a few thick lengths of bus bar. Or even heavy copper pipe. What you want is a lot of surface area for the reaction.

No, there's not actually enough silver in plated jewelry or silverware etc to make it worth 'stripping off'. Same even goes with gold plated, profit ratio isn't there.

The nitric acid is used up during the process leaving the remaining solution which is silver nitrate. The silver nitrate then exchanges ions with the copper yielding the silver cement and copper nitrate solution.

I got lucky and found this one locally, but you can order them online. If you don't get one that vents to outside, just make sure it uses a good quality carbon filter. The carbon filter on this one is massive and weighs about 40 lbs. Still be sure you're in a well ventilated area.

Yes, you can use more concentrated nitric acid to speed up the process, but you'll still want to use some diluted acid for better volume and control. Start with diluted, then add more concentrated throughout the process.

Hi, no the exact ratio doesn't matter. I used about 450g in copper wire, and the silver nitrate was comprised from ~950g of sterling silver. I believe copper can refine around 3x it's weight to sterling silver.

Yes, in fact copper is what predominantly makes up the other 7.5% of Sterling silver.

@@JoshuaAndersonLife Thanks Joshua, I really appreciate the reply. I've Melted sterling bars and then I've an 800 (ish) bar melted also (turns brown with acid test). If I stick all in at the same time and use your set up almost identically, should I get a .999 result? I think what I mean is "Is there anything the 70% solution won't dissolve into vapour?''

@@jackryan261 Yes the nitric acid will take care of virtually everything in the refining process. Technically this process is only getting closer to a .995 and you need to do a second phase with a silver cell to get to .999+.

@@JoshuaAndersonLifeThank you. Step by step, the crawl begins.

@jackryan261 Post your progress 👍

I used right about 1 L of nitric acid.

Video is 2 yrs old but I am getting into smelting, if you’ve still got your silver I’d be willing to do this and return pure silver

I live right in your area

Gifts or post them now and then.

Sorry, I am not sure how you would recover the initial copper that is removed from the Sterling silver. However, it would not have much value.

If you add iron to copper nitrate the copper will plate out on it. But it will need to be further refined.

If you add zinc metal or iron metal into the copper nitrate solution, then the Redox reaction will produce metallic copper powder as the zinc metal or iron metal dissolves.

I keep the heat top on 'medium' or 3 out of 5.

Hi, that's just too burn off any dirt, wax, grease etc before breaking it down in the acid. It's not totally necessary but it helps when you're filtering it out later.

@@JoshuaAndersonLife That's good, my dear friend. 😊👌

Can you put up a good video of the electrolysis stage

@@jameshuse8573 sure when I get home if I have time ill show my silver cell

What if u take it and pour it in tap water to make the chlorides? Then would it be 3 nines? I mean if it’s been refined once with distilled water. I can clean it with tap to get the nitric off and melt?

My understanding is you're supposed to use distilled water because tap water can cause a reaction resulting in decreased purity.

No, melting it down will not actually change the percentage of silver to copper ratio. It needs to go through some form of a chemical refining process such as this.

Right around 1000 mL of nitric acid.

@@JoshuaAndersonLife thanks

@@francesc517 👍👍

👍🙂

@@JoshuaAndersonLife And It's greatly spectacular example of such magical chemical reaction! :D glad I have found it XD Make a video only about that, youtube algorhitm would be crazy about it :3

It uses a carbon filter...

@@JoshuaAndersonLife ok I never knew you could filter out toxic fumes. I need one of those!

@@meanboycoins6250 Good quality fume hoods will use a very large nearly ~50 lb carbon filter. In addition I use it in a well-ventilated area.

You don't. You use copper to drop the silver out and filter that from the remaining copper nitrate. His final product is not .999 more like .985. He needs to further refine it with a cell to separate the remaining copper and any other metals from the pure silver.

I'm going to make another video, and I'll cover that.

😆

@@JoshuaAndersonLife DO YOU OFFER A SERVICE LIKE THIS? I HAVE A BUNCH OF RANDOM SILVERWARE SALT SHAKERS ECT T HAT I WOULD LOVE TO REFINE AND KEEP.

It's really more of a hobby... You have to get really good deals on sterling silver to make it worth it. If you pour quality silver pieces however people will pay a good premium for those.