# Problems in the AP methode



## frank-20011 (Sep 1, 2015)

Hello everyone,

this is my first thread here...I am from germany, 34 years old and if you can see it on my joining date, I've read here for a while and I safe goldscrap since almost 2 years.
I am not unexperienced in chemistry, I've studied a nature scientific and thus I have a lot of chemicals and safety stuff at home and so I haven't to buy anything.
One pray: english isn't my mothers language and so I wish you: please ignore my faults and my crude english skills....if there are anything absolutely unclear, please feel free to ask me what I've mean!

O.K. I assort my material in different "groups": Fingers and plated boards for AP, ceramic IC's for AR, plated pins for sulfuric cell and so on and in the time I make more studies I will use these time to process my fingers and plated board parts in the AP solution at first, i thought that "should" be the easiest and safest process and I've looked a lot of vids, read the posts (the problem posts too) and the tuts.

I've started a big 3l glas with almost 4lbs of the plated boards and fingers, for beeinig safe and without loosing gold in the sollution I put a lot of tap water in it, only 50-100ml HCl (30%) and ~5ml H2O2 (30%) and ~10g CuCl, let it stand over night an nothing hapend, the slt.solution is almost colorless and no fingers swirling arround.
This is not strange because the low concentration of the chems but I was wondering about some fingers who get silver, grey or almost black.
On some trim eges, solder points growing copper sponge (I Know: the material should bee as clean as possible and so I take of al components and as lot as possible of the solder but if there are boards they are plated and assembled, you can not exclude every soldering point)

O.K. I've started bubbling air trough it and put a little bit of HCL and H2O2 i it...after 24 hours it looks like discribed above again and so I take a few of the boards and fingers out of the slt solution and pull them in a 750ml glass.
I start a new slt. solution which consits of 300ml tap water, 300ml HCl (30%) and 15ml H2O2 (30%).
This is 1/2 of the concentration which I take out of the vid from feeds which is 3:1 (HCl 31% and H2O2 3%).

The rxn reactionstarts rough, the color of the slt gets yellow and then emereld within 10 mins and the first fingers starts floating. I am in fear, it's much to fast, much faster than I've seen it in the vids and so I take out 2/3 of the slt solution and replace it with water...in the stronger part of the slt solutionI put 2 of the fingers from the thinner slt solution and they where dissolved within 2-3min but why?

My slt. solution is half as concentrated like commended....next problem: after 1/2 hour I can see like copper crystals start to grow like in the big glass, everywhere: on bare copper on the trim edges of the boards, on soldering points....and so on.

Why are the rxn reaction so fast? why gets the gold in the slt solution and why grew there these copper crystals?

Thanks a lot, regards, Frank!


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## solar_plasma (Sep 1, 2015)

if you mean reaction, then write reaction...same for solution

If you have CuCl like you described, you don't need to add H2O2. Just dissolve it in your strongest HCl and you are left with CuCl2. Don't be too afraid of dissolving some gold, - if it really dissolves, it will cement back and end as dark brown or black powder in the filter.

Small amounts of tin will not harm too much, though it is wise to avoid, if possible. It will deplete the solution from some copper - stoichiometrically seen, next to nothing.

Don't use that much water. I use full concentration (24% HCl...I wouldn't use smoking HCl either) and the only reason to dillute it, that I can see, might be that you have to cover a lot of inert material with the solution.

You need to have a good plan on what to do with the waste solutions!


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## bswartzwelder (Sep 1, 2015)

A 30% solution of H2O2 can dissolve gold. Here in the US of A, 3% H2O2 is readily available and cheap. If you need to make a new batch of copper chloride leach, it's easy enough to do. Just add you HCl to the container you'll be using and add a little bit of the old (used) copper chloride leach. You should never need to buy more H2O2. Another thing to do is to place scrap steel into the used copper chloride container. It will cement out all the copper which has been collected by the solution.


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## frank-20011 (Sep 1, 2015)

Hihi,

and thanks a lot for your replys!

Mhmm...I think all of you know the videos from the goldsmith "Manfred Manteufel"...in his "Cellphone Gold" Video:

https://www.youtube.com/watch?v=Wut1aL4S6tk

you can see at 3:30 how less H2O2/HCl he put in how much water....after seeing that I use such a driblet like he.

In europe the 3% H2O2 is the standard type and after the beautiful "APEX-Abkommen" it's nearly impossible to get the 30% version (ore HNO3 over 3%!!!!!, any nitrates, any chlorates....Aceton in higher amounts and so on) but I have 0,5l of the 30% version in my fridge, think about: this half liter is 5 liter of the 3% version so I safe a lot money, space and in some cases you need higher percentages.

O.K. you wrote: 

"A 30% solution of H2O2 can dissolve gold" and I've wrote it in these forum on an other place too (the same statement) but it's wrong: I do not use 30% H2O2, I use 15ml of H2O2 (30%) in 600ml H2O/HCl and so I get an solution of 0,75% H2O2, the same like in feets mix: HCL : H2O2 (3%) in an 4 : 1 or 3 : 1 ratio!

At first all then solutions where used over the years and refreshed, if they are too much, here we have an urban receiving office where I can bring the hardest stuff for free and they dispose it over special companys so that is no problem!

I have no CuCl, I solved a piece of copper strand direct in HCL and 30% H2O2....

I hate the HCl fumes, but like solar wrote the 24% version seems to do not smoke as much as the 30% HCl.

O.k. tomorrow I will start a new batch...HCl ~25% and H2O2 3% in an 1:3 ratio cause now my solution looks ugly again: there are so much copper crystals....I don't understand it, get the copper out of solution cause there are so less chemicals in it, I starting bubbling again but there ar mm thick copper crystals on tin, an copper and on gold fingers too, I scratched the copper from the fingers and there are plain shiny gold underneath.
The solution itself is only weeeaaak blue.

Thanks a lot, nice evening, regards!


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## lanfear (Sep 1, 2015)

frank-20011 said:


> O.k. tomorrow I will start a new batch...HCl ~25% and H2O2 3% in an 1:3 ratio cause now my solution looks ugly again: there are so much copper crystals....I don't understand it, get the copper out of solution cause there are so less chemicals in it, I starting bubbling again but there ar mm thick copper crystals on tin, an copper and on gold fingers too, I scratched the copper from the fingers and there are plain shiny gold underneath.
> The solution itself is only weeeaaak blue.
> 
> Thanks a lot, nice evening, regards!




The problem with your AP is not your ratios of HCl and H2O2. You simply have to little free HCl in the solution to hold the copper in. And therefor is get's pushed out and crystallizes.
Start a new batch and use only HCl without water. But don't use a 1:3 ratio!! Use 2,5 liters of HCl and 50ml of 3% H2O2. That is all you need.

Jon


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## g_axelsson (Sep 1, 2015)

I'm not impressed by that video and I have never seen it before. He filtered off all the junk with the gold that came off the cell phone boards. Then melted the filter with a piece of copper wrapped around it. Next step seems to be leaching away metals with nitric acid and melting the gold powder, kind of inquarting but with a lot of copper.

You can't tell anything about the amounts of chemicals used as he doesn't tell and he adds more acid later on in the video (or just mentions it in text).

I would advise that you forget about ever seeing that youtube video. 

Here is a list of videos made by forum members who knows what they are doing.
http://goldrefiningwiki.com/mediawiki/index.php/YouTube

Your copper is cementing back onto metal parts of your boards as they contains other metals than copper. Tin for example goes into solution while copper cements out on exposed metal that is in electrical contact with the tin. It's basic electrochemistry and it will continue until most of the solder is dissolved. That's also the reason that your solution loses it's color.

CuCl2 is easily dissolved in water while CuCl is almost insoluble. We add HCl both for dissolving the CuCl that is created when we dissolve the copper from the boards and as a source of Cl to refresh the leach. With too little HCl the CuCl starts to precipitate as a gray to white sludge, as can be seen in the video you linked to. Some of the sludge could also be tin oxides and lead chlorides. Any silver in the solder would probably be converted into silver chloride too as it's so finely dispersed. A hint in the video is that the sludge in the filter is turning purple.

I recommend that you spend a month at least, just doing research on the forum about the copper chloride etch method.

Göran


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## g_axelsson (Sep 1, 2015)

lanfear said:


> frank-20011 said:
> 
> 
> > O.k. tomorrow I will start a new batch...HCl ~25% and H2O2 3% in an 1:3 ratio cause now my solution looks ugly again: there are so much copper crystals....I don't understand it, get the copper out of solution cause there are so less chemicals in it, I starting bubbling again but there ar mm thick copper crystals on tin, an copper and on gold fingers too, I scratched the copper from the fingers and there are plain shiny gold underneath.
> ...


Metallic copper doesn't get "pushed out" if the ratio of HCl is too low. To get metallic copper you need to reduce the copper salt. In this instance I guess that it is reduced by tin, led and other less noble metals that is oxidized.

Reduction : Gaining electrons
Oxidizing : Loosing electrons

If you run out of HCl then CuCl starts to precipitate as a white salt, but it's still copper chloride.

Or as chemists would write... Cu s + CuCl2 aq  -> 2 CuCl s 

Göran


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## frank-20011 (Sep 1, 2015)

Hihi,

and thanks again.

I Know the nexus between CuCl and CuCl2, but I thought that the little bit of my home made CuCl with fresh HCl in the big glass is enough to start the reaction contemporary.


"I'm not impressed by that video and I have never seen it before. He filtered off all the junk with the gold that came off the cell phone boards. Then melted the filter with a piece of copper wrapped around it. Next step seems to be leaching away metals with nitric acid and melting the gold powder, kind of inquarting but with a lot of copper."

Yes,....and on the board there are all the capacitors, resistors...to be honest, I thought that is not the badest idea to wrap the filtern paper in THIN copper so you can not blow it with the burner but you don't get a good product in one cleaning step!
His german is.....and I think it's his mothers language!
But to the Videos: I think he is unexperienced, he is an goldsmith and do this reactions only for fun, his silver cell isn't bad but I agree with you: most flaw is the lack of a discription, ratios...etc.

"Your copper is cementing back onto metal parts of your boards as they contains other metals than copper."

But it cements out on bare copper too!
And if there are no tin, no iron, no braze contacts, there are gold...I!!! think that coult not be the only reason!


"Here is a list of videos made by forum members who knows what they are doing."

I will look them carefully (if I've done it)!

O.K. thanks a lot....nice evening!


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## g_axelsson (Sep 1, 2015)

frank-20011 said:


> "Your copper is cementing back onto metal parts of your boards as they contains other metals than copper."
> 
> But it cements out on bare copper too!
> And if there are no tin, no iron, no braze contacts, there are gold...I!!! think that could not be the only reason!


That is the only reasonable reason for copper to cementing out. If the metal is in electrical contact with tin then copper can be cemented out on gold or bare copper.
You wrote:


> On some trim edges, solder points growing copper sponge (I Know: the material should bee as clean as possible and so I take off all components and as lot as possible of the solder but if there are boards they are plated and assembled, you can not exclude every soldering point)


It is enough if one of the solder points is touching a wire, then copper can cement out on copper or gold connected to that wire.

There is no other reasonable explanation for copper to cement out of the solution as metallic copper.

Göran


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## frank-20011 (Sep 2, 2015)

Hello,

thanks again.

I have bought 1l of HCl 23% and a 100ml 3% H2O2 for 4,5 bucks today so I will start a fresh batch.
In my two glases since yesterday nothing happpend, only more copper Crystels grew...almost 2mm thick.

The fact with the thin sounds plausible but I am not shure...I think there are cutted fingers with copper crystels too and there are not one atom of tin on the whole piece of the part of the board!

The other observation deals with the silver fingers, what is going on with these Fingers?
There are whole stripf of former boards with a lot of fingers on it, a few of them looks golden, other ones are silver, and there are no foils...whats that?
Is it nickel? Is the gold gone on these fingers or is this some kind of reduced metall? maybe tin?

What should I do? Should I etch the tin before in HCl or should I only start with H2O2 and Hcl?

Greetings!


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## Geo (Sep 2, 2015)

Das Video ist ein schlechtes Beispiel für die gezeigten Prozess. Sie sollten sich nicht mit Säuren in einem Gebäude ohne gute Laborkontrolle arbeiten. Verarbeiten ganzer Handy-Boards ist keine gute Idee. Mein Video auf YouTube,zeigt, wie die Komponenten mit heißes Sandbad entfernen. Die Platten und die Komponenten werden getrennt verarbeitet werden. AP oder Kupfer (II) -chlorid ist sehr einfach zu tun, wenn Sie lernen, wie man es benutzt. Sie müssen nur Wasserstoffperoxid nur einmal verwenden. Nachdem Sie Kupfer (II) -chlorid erstellt haben, können sie immer und immer wieder verwendet werden.


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## frank-20011 (Sep 2, 2015)

Hello everyone, 

und danke Geo, dass du dir die Mühe machst to write in german...I know all of your videos (and your horrible nitric acid experience!!!) and the facts about the Ap-methode you've listed I know too!
The Video I have linked Isn't my one and on my boards which I want to process in AP there are no single one compnent and the tin-solder I've melted I sling from the board to....your idea with the sand-bath is very timesaving but I am working with a burner or a hot-air gun, that's fine too!

...working in an apartment isn't easy, and a window isn't a exhaust hood, working with less higher concentrated HCl, H2SO4 especially an a balcony is acceptable... for working with nitric, hot acids I go outdoors!

Mhmm...next problem: today i've fished the boards out of my solutions and start them again how I've described in my last answer: only 23% HCl and 3% H2O2 in an 20:1 ratio.
The liquid turns yellow fast, after 5 minutes they gets emerald but after 10 mins more they've get colorless again.
Mhh...puuhh...seems to bee much, much to much solder, and if I look the Video I've linked I don't understand how these guy get an emerald solution and swirling gold flitters cause he process ONLY cell phone boards WITH the components and WITH the whole tin.
I process pieces of boards whithout any soldering point, clean fingers and only a few cell phone boards and they are free of any! component and almost free of the tin!

O.K. now I am clueless again...should I wait until the free HCl has solved any tin?...Is this expectation realistic?
Is there enough acid to solve the whole tin and the solve the copper?

What's with my question about the silver fingers...why there are silver colored fingers nearby golden ones?

Thanks a lot regards...Frank!


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## lanfear (Sep 2, 2015)

g_axelsson said:


> lanfear said:
> 
> 
> > The problem with your AP is not your ratios of HCl and H2O2. You simply have to little free HCl in the solution to hold the copper in. And therefor is get's pushed out and crystallizes.
> ...




Thanks for clearing that up Göran. I still have allot to learn and I learned something new today.
That is one of the best things about this forum. You learn from all mistakes.

Jon


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## Geo (Sep 2, 2015)

If the solution is forced to dissolve more copper than it can hold in solution due to oxygen saturation, the copper will precipitate out as CuCl. If the free HCl is used up in the reaction, the copper will precipitate out as copper oxide with some copper hydroxide if the PH is high enough. When your AP is very dark or brown looking, it is copper oxide.


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## frank-20011 (Sep 3, 2015)

Hi,

the solution is clear, and almost colurless, I do not know the pH but the fumes,or in this case better the smell of the solution tell me there is enough HCl in it.

I guess I have too wait until the solder is solved...the the copperetching starts (again).

An other fact I didn't understand is that the liquid first turn emerald, like it should be...the they gets clear but there are tin and other metals since the first second...

Do anybody use sodiumpersulfate to etche copper...is ist possible in our cases?

I future I have to clean my material much, much more carefully!

Should I only wait or should I change anything and sorry about repeat my question with the silver fingers, why turn they silver?

Greetings!


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## Geo (Sep 3, 2015)

The tin takes on a positive charge when it dissolves. The gold plating is in contact with the reaction and either has a neutral or negative charge. The positively charged tin is attracted to the negatively charged gold. Think of a car's battery. The chemical reaction in the battery is what gives the battery it's positive charge making it able to start your car.The same reaction is happening when you dissolve the tin solder. The gold plating is still there but it's coated with a thin layer tin metal. This can be wiped or rubbed off but there's really no need to do it.


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## frank-20011 (Sep 3, 2015)

Hihi,

I hope it...

I was concerned about that strange looking fingers: I have the cuttet board stripes with the fingers on it a few of them looks golden, others copperish and the last one looks silvery, shiny and these silver coating adhere very well to the underground: it can't be wiped off even not scratched off with the fingernails and so I think on an nickel coating.

You mean I have only to wait until the point is reached where the tin is gone and copper starts again with etching?
(I think a lot of the tin is gone untill now and on a few places on a few boards I've take out off for considering the copper is gone too untill the bare sythetic resin!)

I have warmed up the whole mass with an aquatic heater...to 50°C...ehhm 120°F.

Regards Frank!

P.S. it's right to write "problems -in- the AP" or should I write "with"...?


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## frank-20011 (Sep 3, 2015)

frank-20011 said:


> Hihi,
> 
> I hope it...
> 
> ...



P.S.S. sorry but I think I'm not the only one who will process gold plated boards which have a plating on one side and a lot of tin solder points on the other (like on cell phone boards at the keyboard area) how process you these? Maybe it's better to pull em in nitric instead AP?

regards!


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## lanfear (Sep 3, 2015)

frank-20011 said:


> P.S.S. sorry but I think I'm not the only one who will process gold plated boards which have a plating on one side and a lot of tin solder points on the other (like on cell phone boards at the keyboard area) how process you these? Maybe it's better to pull em in nitric instead AP?
> 
> regards!



No. If you put them in nitric you will get metastanic acid from all the tin. This will trap your gold in a grey gooey mass and make a big mess. The best thing to do is to dissolve the tin with HCl and then start a fresh batch of AP. The HCl you can save for more tin dissolving later on.


Jon


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## frank-20011 (Sep 4, 2015)

Hello everyone,

today I take the parts out of the big beaker with the thin acid, washed them and then I seperate out all the boards they have more solder points than golden areas (like cell phone boards), the rest consists of clean finger stripes and boards with less solder points.
I cut of almost all soldered areas (like I should it do before I start) and put these parts with the fingers in an new glass...the "much solder" parts go back to the filtered solution.

Filtered out parts are a grey sludge and very sparkling parts, like crystals, I think this all is tin, reduced by the copper/gold but no flakes.

A few boards, again and mainly phone boards, go to the litter box because there is no visible gold anymore, the prior gold plated areas are silvery now and these coating is very good adhering and smooth (nickel?) so i couldn't find any trace of gold under it...only copper and this is the same case with some other boards...I think these are very thin plated parts, I've read that particular for newer cell phones and so my linked video must be a fake above all he get very nice flakes, big flakes, no gold sludge and from 11 phones more then 1gr...I've read an average gold contend for one cell phone is 25mg or rather 32mg (in an other text).
Next factor is that my boards are much! much! cleaner as his ones and the bullsh... with these boards i my first AP-try you know now.

The silvery coating on fingers, its more a grey/black and not very evenly, I can scratch indeed and there is goold underneath...

O.K. tomorrow I will fill the glass with cleaned parts up with fresh AP and then I will cary all three glases (1st glass with the thin acid and the -much tin- parts, 2nd the glass I have started on sept 2nd) outside on a place where I can not see them and let they stand for...for at least one week before a take a look on them again!

Apropos the beaker from the 2nd of sept: there are floating some flakes on the surface but there are tin solder points by now and the liquid is colorless by now too!

Then I will reports what happend.

P.s. now I've read the AP instructions again and so I know I've made an other mistake: I've pressed much to much parts in my beaker!

Nice weekend!
Frank.


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## frank-20011 (Sep 5, 2015)

Hi,

today the liquid in booth pots is yellow (I've startet this morning the cleaned parts again, like I've discribed yesterday) but when I drop a few drops of H2O2 in it it turns first emerald, then yellow again, means that it's to much tin inside or it's to less O2 inside?

Thanks!


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## g_axelsson (Sep 5, 2015)

Either you have too little copper chloride so the copper cements onto other base metals and the yellow look is iron chloride left in solution, or the copper chloride is very weak but working and goes from green copper II chloride into brown to yellowish copper I chloride because there is no oxygen left to turn it back into copper II chloride.

Try to pour off a sample into a beaker without any metal in it. Oxygen from the air will turn it green again in a while, you can watch it from the side to see if there is a green layer closest to the surface. A bubbler, a few drops of H2O2 or pouring the liquid between two beakers a few times will speed up the process.
If the liquid doesn't turn green again when there is no metal you don't have any copper I chloride in solution, any copper in solution have cemented back onto the lesser noble base metals and you have basically just hydrochloric acid.

On Lazersteves website there is a document with the colors of various concentrations of copper chloride. Look at that and you will see that it takes just a tiny bit of copper chloride to get quite a strong color.
If you haven't done it yet you should read through that document a couple of times until it mostly makes sense.

I've just started a small experiment by sticking 42 ram sticks in a beaker with pure HCl to remove the components. So far some of the fingers have turned into small silver mirrors while the next finger could be shiny gold.

Göran


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## frank-20011 (Sep 6, 2015)

Hello everyone,

"silver mirrors while the next finger could be shiny gold."

yep, exactly.

And as you've suggest: a drop peroxyde in the solution and the liquid arround the drop turns immediatly green...a little bit of the solution in an test tube, waiting and shaking and it turns in a nice emerald.

O.K., now it works with much more air...some nice gold flakes.

My main mistake is that I was so fondly hoped that it work that I've started all in one, the badly cleaned boards are an other thing! 

Thanks to anybody.

Nice weekend!


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## frank-20011 (Jan 26, 2016)

Hello,

i'll not start a new thread because the actuel problem deals with the ap methode too:

after processing some processor sockets and smaller IC sockets in AP all the copper is gone, the gold is settling down in the vessel and so I collect the used AP-sollution with some crystal needles in it (maybe Pb and other metal salts) but between the gold and the clear (better almost clear) AP sollution there are a grey fine sludge, all washing with hot water is useless for dissolving these strange, cement looking stuff.
After a few washings the water is colorless but the sludge remains, an other problem is the finer gold flakes are catched in the sludge so it isn't impossible to suck these waste in a syringe or something.

I try to dissolve the sludge with HCl, hot water...nothing happen.

What can these fine bul... be?
How co i discard it?

The connectors i've processed are older, so the solder composition changes to the solder they are use today and i know nothing about the base metal compositions so i haven't any inkling about these cement-looking sludge.

How can i continue?

Regards!


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## g_axelsson (Jan 26, 2016)

My guess on the grey sludge, metastannic acid. 
The forum is full of tips on how to deal with it.

Göran


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## frank-20011 (Jan 26, 2016)

wasted letters


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## frank-20011 (Jan 26, 2016)

Hello,

i thought abouut metastannic but i think meta is more like a gel...if it's really meta i cuold easy dissolve it by adding KOH/NaOH or according to hooke it's soluable in H2SO4 (i will make a little test in a test tube***)

It looks exactly if you put cement in water an let sit it for a while...water above is clear and the heavyer mieralic parts stay under these clear water.

is it true? looks meta like gel?

***if it's really metastannic i have a few possible methods to solve it but because my flakes are mixed with a lot of coating pieces from boards the lye method should be the best: lye dissolves the green varnish AND meta?!



Regards, Frank!


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## Geo (Jan 26, 2016)

Aluminum chloride is a gel. How much aluminum was in the mix.


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## frank-20011 (Jan 26, 2016)

Hello,

my bad english...no AL was in the base matals...I devised only that metastannic looks like a gel...the substance in my vessels isn't a gel, it is like a mix of very, very fine gray looking sand and water, after a while the "sand" sits down on the bottom of the glass and the clear water is above the "grey sand".

after a little bit of reading i thing the grey sludge (not a gel, i only think meta looks like a gel) is meta and so i will now make a little test with KOH.

Sorry for my bad english, every time again!

FranK!


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## frank-20011 (Jan 27, 2016)

Hello,

i've made little tests with NaOH and H2SO4 and nothing happend...i've looked for some pictures from metastannic and my sludge looks like it but as said: no reaction!

Regards!


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## UncleBenBen (Jan 27, 2016)

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=85&t=22375#p234040

This is Harold's thread on incineration. If the sludge is tin, it will be soluable in HCl after being properly incinerated.

If still insoluble after incinerating, its something else. Try to dissolve a small amount in AR or HCl/Cl. If still insoluble, dissolve your gold and filter out the sludge.


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## frank-20011 (Jan 27, 2016)

Heyhey,

i know about incinerating of metastannic but I think! if this gunk is metastannic, it should 

-dissolve in strong lyes (like NaOH)
-dissolve in strong H2SO4, like Hoke wrote... (both are heated)

and both do not happen so why should I incinerate....

I thought that it is maybe something organic, in this case incinerating is the best method....mhm strange!

Regards and thanks!


(at first i've tryed HCl, maybe I should try HNO3 too?)


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