# My first silver buttons!



## philddreamer (May 8, 2010)

I'm sharing some photos of a succesful process. 
I thank all the persons that have shared from their expertise & made this possible. I thank Juan Manuel for sharing his silver refining formula from which I used some steps & pointers.
I had one small problem & I know someone will have an explanation for "why". I started using table salt to drop the silver, but there was no reaction what so ever. After adding 50g I stop & used HCI instead. No problema! 
Continued with the steps, using lye; I used sugar like Juan Manuel recommended & this is the result. I started with 190g of sterling scrap; ended with 180g. 
These are the first melt, 30.7g & 61.7g. 

Once again, I thank you all!

philddreamer :lol:


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## machiavelli976 (May 8, 2010)

nice pills ! at 190g of sterling you should got 175.75g of nearly pure silver. 180 means some AgCl trapped inside. however is a good result for an first attempt. try copper cementing. is not so fast but entertaining enough.


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## machiavelli976 (May 8, 2010)

another thing. you might have three reasons for failling with table salt: 1) your table salt is not quite NaCl, so beware ! 2) you got excess of nitric in solution, and 3) you got both 1) and 2).


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## Anonymous (May 8, 2010)

I notice the bubbles from oxygen, how do you prevent them when casting silver?

thanks
Jim


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## philddreamer (May 8, 2010)

Hi machiavelli!

Thanks for your observations. There's another posibility for the extra silver. I didn't mentioned that some of the scrap was .999. Just a few items. Some made in Mexico only said "silver", so that's why I wasn't surprised for the extra. Sorry! I should have been more specific with the info. I gave.
The salt was my concern or curiosity. Maybe the salt I bought this time is not quite NaCl. though is the same brand, Morton but withiout iodine. Yet, as soon as the first drop of HCl hit the solution, cottage cheese! 
Too much nitric, maybe. The reaction stopped @ ambient temp., so I heated up the solution & reaction intensified. After 40 minutes it slowed again. At this point I added about 150ml of 50/50 to the Ag saturated solution. Reaction started & went on for another hour. I let it cool, filtered & proceeded with the salt.

Yes, I will experiment next batch cementing with Cu. It's 3 oz left over from inquartation.

Thanks! 
philddreamer


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## philddreamer (May 8, 2010)

Hi Jim!

I don't remember. I read some weeks ago & saw some photos about the subject. Yes, it's oxigen & if I recall correctly one can minimize that effect by letting it cool slowly. I'll be searching the posts. I'll let you know or you let me if you find it first.

Thanks!
philddreamer


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## shyknee (May 8, 2010)

philddreamer 
ok very good you got the silver but the buttons ?.. some thing is not wright.
i think you never got it totally melted ,you have to keep the heat on it longer or hotter try remelting you will see when it all comes together.
good luck


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## philddreamer (May 8, 2010)

Jim, 
on the board index check into silver, post: casting silver bars, by p_carroll.
It's a start. I'll be e-mailing Juan Manuel for some more details.

phil


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## philddreamer (May 8, 2010)

Hi shyknee!

I did melt it. I used a acet/oxi torch, & it was a beatiful smooth shiny button.
I took the torch away slowly & covered the dish with a fire brick, so it would cool slowly. Then a minute or 2 later I heard a hiss for about 30 seconds. I was surprised & wondered how did water get in there? That's when a remember about a reaction of silver with oxigen. There're some post on the subject & I'm seaching. 
Brother james122964 has the same question.

Shy, if you know, point us on the right direction please. 

thanks!

philddreamer


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## g_axelsson (May 8, 2010)

This is only a suggestion as I haven't got an acetylene/oxygen torch to test with. No guarantees given.

Try to remelt it with a reducing flame to keep any oxygen from dissolving in the molten silver.
Don't keep it molten for longer than necessarily. Then turn down the oxygen and protect it with a sooty flame, the carbon in the soot should keep any oxygen away. When it has solidified it is safe to remove the flame.

I've seen the effect myself and the first time you see it it could be quite dramatic.... a 1000 C fizzy drink.

/Göran


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## philddreamer (May 8, 2010)

Hi Goran!

Thanks for your suggestion. I did something similar to that while melting.
I'm welder, so I took precuations so not to contaminate nor let cool too fast.
But from the info. on several post I learned that silver has an affinity to oxigen. I'll keep searching in the "Silver" threads. If you find some info. please let us know.

Thanks Goran!

philddreamer


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## shyknee (May 8, 2010)

oxy yes i do remember a post about that that is why i only use the Mapp gas no oxy saves me money.


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## philddreamer (May 8, 2010)

there's another post by harold in "silver" melting down sterling. It shares more light to the matter.

Yes, I started with mapp but ran out & out of desperation used my acet/oxi torch. We live & learn. :shock:


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## philddreamer (May 8, 2010)

Right here in "Gallery" check - my first silver loaves. HTP puts the slugs in cold water before the oxigen gets a chance to react.


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## qst42know (May 8, 2010)

Silver absorbs oxygen while molten and expels it while solidifying. You need a large enough flame that is rich in fuel to consume oxygen and shield the silver from the air while it is molten.

Some charcoal in the dish can help.


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## philddreamer (May 8, 2010)

Thank you qst42know!

I read on another post that some sugar with the borax also helps. What is your experience with that? 
So, these then will help by consuming oxigen while silver is molten. I get it. The oxigen needs to be control while molten. Not with argon or co2 as it cools?

The charcoal in small pieces? & in what ratio with the borax?


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## qst42know (May 8, 2010)

It would be best if you could do this with an oxy/fuel torch adjusting the flame to be rich. Much cleaner.

With a self aspirating torch (fuel only) it's not easy to do. You may try covering some of the air intake holes on the torch but it won't get as hot. You might also try inverting a second melt dish as a cover.

There is a sweet spot in any torch flame you can find this distance by heating a clean piece of steel till it starts changing color note the distance at which the flame keeps the steel from turning blue. That's where the flame is shielding the steel and that is the distance you want to maintain while melting.

Sugar, flour, or charcoal can help but you risk including some ash in the pour.


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## goldsilverpro (May 8, 2010)

I haven't heard any mention of temperature. Those buttons look like they got too hot to me.


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## philddreamer (May 8, 2010)

I will be taking all this detail into account! I appreciate you taking the time & helping me out, qst42know.

GSP has another detail I didn't consider. 
Hi GSP!

What is the recommended temp & time of heat'n silver? The temp of the molten metal is what causes the oxigen to be absorbed into the silver?

& will slow cooling help in any way @ all?

Thanks!
philddreamer


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## goldsilverpro (May 8, 2010)

Just get it hot enough to thoroughly melt. Then, if you can play a cooler torch (or draw back the flame progressively) on it until it slowly solidifies, you should have a much smoother surface - use a reducing flame for this. It's really easy to overheat small buttons with a torch. 

The idea that qst gave about inverting a second dish (or ceramic or graphite plate) on it should work too. This is commonly done in fire assaying, using a hot cupel as a cover, to prevent sprouting of the silver. This works best if the covering dish, or plate, is about as hot as the melting dish. Don't lift it until the button has completely solidified. I have lifted the covering cupels too early (when the bead is still barely molten) and actually watched the bead sprout as it quickly solidified. I learned to just cover them and and then come back 10-15 minutes later. The beads were then solid and smooth. 

I think either procedure allows the oxygen to be eliminated slowly as the metal slowly cools, rather than all at once. The slower you cool it, at least until it has completely solidified, the smoother the surface. That's been my experience.

I think I've read that, the hotter it gets, the more oxygen it will absorb, at least to a certain limit. And, the more it absorbs, the more it has to expel before it solidifies. If it does it all at once, the rougher the surface will be.

If anyone technically knows more about this, please chime in.


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## philddreamer (May 8, 2010)

Thank you GSP!

I will be trying again & better prepared for the task. As a welder, I've had to pre-heat to a specific temp as well as to allow to cool slowly in order for the weld no to crack. This is kinda similar. This is definitely not a wham, bam thank you ma'm procedure, if I may use the expression.
I will continue melting silver till I get it right & post some photos.

I thank you all for your time & patience. 

philddreamer


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## Harold_V (May 9, 2010)

Trusting to memory, silver absorbs nine times its volume in oxygen when molten, liberating it as it solidifies. As GSP mentioned, keep a reducing flame on the silver--that alone will prevent the absorption. 

It was recommended that a covering of charcoal be placed on molten silver, although it seems to me it would be troublesome. 

The addition of traces of copper to pure silver limit its ability to absorb oxygen, but that's contrary to our objective, which would normally be pure silver. 

I agree with not overheating. If nothing else, whether it encourages more or less absorption, it does provide additional time in which it can. If I had to guess, I'd suggest that you'd want to be only about 50° hotter than the molten state, in order to pour an ingot. 

If you're leaving it in the melting dish to form a button, slowly reduce oxygen, allowing the flame to go heavily reducing. If you're using acetylene, allow it to blacken the surface. Remove the acetylene the moment the button freezes, so the residual heat will burn off the carbon coating. 

Harold


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## philddreamer (May 9, 2010)

I thank you Harold for taking the time & sharing with us your expertise on this matter. I've always had an interest in molten metals & learning this technic would be an achievement for me.

philddreamer


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## philddreamer (May 9, 2010)

Harold, 

is it correct to say that this is a sign of purity, since adding a bit of copper would prevent this from happening?


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## Harold_V (May 9, 2010)

philddreamer said:


> Harold,
> 
> is it correct to say that this is a sign of purity, since adding a bit of copper would prevent this from happening?


It is a sign of purity to some degree, yes, but the color of the surface is very telling with silver (and gold), especially if it has been over heated. It forms fire scale readily, so it would have a bronze appearance if it was badly contaminated. I expect that you would see little difference if you had 99% silver as opposed to 999 silver, but I could be wrong. 
One thing is sure---silver, when pure, does not form an oxide scale coating. Flux deposited on the surface would clean the oxide skin, but that doesn't mean the oxides are gone, they're just gone from the surface. 

Harold


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## philddreamer (May 9, 2010)

Thank you Harold!


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## jimdoc (May 9, 2010)

I remembered seeing this on Ebay, if is of use or interest;
http://cgi.ebay.com/Germanium-99-9999-5-4-grams-/170458903150?cmd=ViewItem&pt=AU_Bullion&hash=item27b024726e

Jim


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## philddreamer (May 9, 2010)

It's interesting. 
I wonder if that is used in the making of german silverware, which contains no silver. 
Adding it could solve some of the oxigen effect, like copper those,too, but I wouldn't add it to solve the oxigen "problem" because I want pure silver as the end result. I'll just have to exercise some patience & follow the procedures in the posts above.

Thanks Jim!

Philddreamer


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## Juan Manuel Arcos Frank (May 9, 2010)

Congratulations,Phil!!!!!!!


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## philddreamer (May 9, 2010)

Muchas gracias tambien a ti mi hermano Juan Manuel!!! :lol:


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