# I think I'm losing gold from my solution



## igi900 (Nov 28, 2014)

hi everybody I hope somebody will be able to help me I processed my gold with aqua regia .
to be exact I used 10 Pentium Pro CPUs.
which should give me 10 grams of gold at the end of the process because I read somewhere that each Pentium pro CPU as one gram of gold.
after all the process was done I drop the gold with SMB the gold was dropped and dried and I had about 3 grams can anybody tell me if I'm losing gold during my process.my process was as follows
1)I placed 10 Pentium pro cpu's in a coffee maker.
2)covered with HCl and added a little bit of water let the water and HCl warm up a little bit and then add small addition of nitric acid until exhaustion.
the reaction was fairly quick about 20 minutes until exhaustion was stopped.
3)then I transfer the solution to a beaker with ice in it and put a few drops of sulfuric acid to drop the led
Silver sulfate.
4)then l filtered solution
5)then use the urea to neutralize the nitric acid
6)then use SMB to drop the gold the final residual was about 3 grams of gold from 10 grms anticipated of gold.
please let me know if I'm doing anything wrong and why I got only 3 grams of gold from 10 Pentium pro cpu's.
thank you very much


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## AndyWilliams (Nov 28, 2014)

Lol, some things never change!

Igi, it's ironic that your post was one of the first I read today. I've been absent for so very long! You need to stop and read. There is a lot that you don't know about recovering your gold, that much is apparent. Your process has flaws, and there is more you should be doing to see where your gold might be. 

But first, save all of your solutions. There is likely to be gold in each of them because you did not drop all of the gold. The gold will still be available to you, but you should start with a reading of this forum or Hoke's book.


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## the iron dwarf (Nov 28, 2014)

read hoke and the forum
do not discard your solutions 
do not believe internet gold yields

lots of people post on the internet about gold content of chips so they can then sell them for more, I have even seen 3 grams quoted before.

there are posters on here who have listed gold THEY have recovered

0.3 g sounds more reasonable to me


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## bswartzwelder (Nov 28, 2014)

What did your stannous chloride test reveal?

edit: Just so that you know. I see that you posted this same question twice. That's very much frowned upon.


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## necromancer (Nov 28, 2014)

I read somewhere that each Pentium pro CPU as three grams of gold, please do not believe everything you read on the internet
how much did you pay for the 10 cpu ?


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## artart47 (Nov 28, 2014)

Hello igi900!
The members that talked about all the wild claims of gold content in cpu's are correct. Just to give you an example, a year or so ago I processed right around 8 pounds of ceramic cpu's wich included a few pentium pro's. I remember the claims from the internet and the verious content charts that were floating around. I also estimated the content from post that my friends here had reported. I figured realistically to refine around ten-twelve grams base on my forum search. If I had listened to all internet B.S.I would expect 2x-3x the amount. After processing washing and melting there was alittle over 9grams. I still have the left over debris and suspect there could be a dusting of gold that a second leach would grab. Almost forgot. There was also a few foils from some of the caps that were gold plated.
Spend some time reading and studying posts of members who are processing your material. There are several things in your post that suggest you should increase your understanding before continuing.
Did you add all the nitric at once? You diden't mension testing for gold. There should be no need for urea! etc...
Hit Hoke's book and the resources here untill you understand what you're doing and why you're doing it. Then you can expect good results and be doing it safely.
Good luck! artart47


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## igi900 (Nov 28, 2014)

I would like to say thank you for everybody reply to this post.
i will definitely read the whole book and try doing it again
about the Stannus tast I did do the tast and thare still gold in the solution what should I do now?


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## necromancer (Nov 28, 2014)

check for excess nitric & then try drop the gold again


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## igi900 (Nov 28, 2014)

thank you I will try that.


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## solar_plasma (Nov 28, 2014)

igi900 said:


> I would like to say thank you for everybody reply to this post.
> i will definitely read the whole book and try doing it again
> about the Stannus tast I did do the tast and thare still gold in the solution what should I do now?



Store the liquids, the solids and the filters safely and, take up this task again, when you have read and learned enough. Enough is when you are sure what exactly to do even without asking any question, though then, questions will be welcome. Cleaning up this type is nothing for the beginner, - just my view.

Until then you should start (after having read) with easy processes like for example fingers. Stannous test is a process of its own and you have to use it a plenty of times in different situations before you feel safe with its results.

I have never tried pentium pro's, but here on the forum I read yields between 0,3 and 0,5 g per piece, so chances are, there might be one gram still hidden even if your first stannous tests are negative.

Probably many of us have started with ceramics, but I would not have gone this way, if I had known, what I know today. Just too many traps.


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## necromancer (Nov 28, 2014)

after studying more remember my edits below.




igi900 said:


> 1)I placed 10 Pentium pro cpu's in a coffee maker. *(crush or break cpu's first & remove large gold plated tops, recover separately for your first few tries)*
> 2)covered with HCl and added a little bit of water let the water and HCl warm up a little bit and then add small addition of nitric acid until exhaustion. *(NEVER add water to acids, always ad the acid to water) adding water to a acid solution should only be done when the in use acid solution has spent it's water, do this slowly*
> the reaction was fairly quick about 20 minutes until exhaustion was stopped. *(experience will tell you when its done, just because a reaction stops does not mean its complete, time will very. you will learn this with experience)*
> 3)then I transfer the solution to a beaker with ice in it and put a few drops of sulfuric acid to drop the led
> ...



i did not fill in all the fine points. please study & make your job easier.


i am sure they will be further discussion.


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## Anonymous (Nov 28, 2014)

igi900 said:


> hi everybody I hope somebody will be able to help me I processed my gold with aqua regia .
> to be exact I used 10 Pentium Pro CPUs.
> which should give me 10 grams of gold at the end of the process because I read somewhere that each Pentium pro CPU as one gram of gold.
> after all the process was done I drop the gold with SMB the gold was dropped and dried and I had about 3 grams can anybody tell me if I'm losing gold during my process.my process was as follows
> ...


I have processed 10 Pentium Pro's this year and from what I yielded and what I've read on the actual yields, you have gotten all the gold you're going to get, if you didn't crush the cpu's into a powder. From the 10 cpu's and if they're not crushed, according to calculations given, there should be around 6g of gold still to be recovered. I finally crushed mine this past week and I'm going to put them in AR today. I'll post my yields on them.

But, if you got 3g of gold from 10 Pentium Pro's, that is what I recovered too. Actually, I think I got 2.6g, out of 10 cpu's total.

Those cpu's are very hard to crush into a powder. 

Also, I was just now thinking about my yields, and if I do get that extra 6g of gold, then, it could be estimated that 1 Pentium Pro would yield around .3 - .5g just as the pdf datasheet estimates.

Kevin


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## nickvc (Nov 28, 2014)

I'm sorry to tell you what you have already heard but there isn't a gram of gold per CPU, for pentium pros the yield should be around .2-.3 grams per piece and that's only if you really know what your doing. Believing anyone else's yields is going to cost you money,only rely on what you can recover and refine, if others can do better let them pay that price.


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## Palladium (Nov 28, 2014)

:roll: 

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=52&t=12845


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## Anonymous (Nov 28, 2014)

nickvc said:


> I'm sorry to tell you what you have already heard but there isn't a gram of gold per CPU, for pentium pros the yield should be around .2-.3 grams per piece and that's only if you really know what your doing. Believing anyone else's yields is going to cost you money,only rely on what you can recover and refine, if others can do better let them pay that price.


I agree totally. But I'm also thinking "*Are the yields from what was visible or were the cpu's crushed down to powder, or close to it?*"

That's why I took notes and I am going to finalize my own findings about gold being hidden inside the ceramics. I'll know from my own experience. On the same note, using other yields as references and then doing can help to get the yields more accurate, according to how you do it, and compare and (or) do another batch to confirm. 

I'm not sure if I read anywhere or not proving for a fact that there is gold in the ceramics or not, but, if I can't find it, I'll know for sure then. If there's gold in them, I crushed 10 of them up very good, good enough to recover gold, if there is any. I'll test my solution tomorrow with my stanous test. I'll post if I test positive or not for gold.

But, the best way to get accurate to average yields you will need to process them yourself. It seems there are always many different yields of things of the same type, yet, important info like if they were actually crushed, ball milled or whatever and if gold was recovered or not. I am going to do a search to see if I can come up on any threads that mention having recovered gold from the inside of the ceramics only. I kept mine (from 5+ months now), so now I know there is no left behind gold from the 1st drop in AR to remove the pins and the inside of the glass or plastic? (black) . If any gold shows up as positive, then I'll know for sure about gold being inside of the ceramics. 

Hopefully there's some gold inside. If not, at least I'll learn from the experience. Either way, I'll post back, and we'll all know for sure, (not unless you still want to do it yourself), if there is gold inside. 

Kevin


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## Anonymous (Nov 28, 2014)

I just found this thread/reply below, so, crushing the pentium pro's has been done.:

*How much gold in pentium pro cpu chip*.

According to the post, there is gold inside of the ceramics in the Pentium Pro's. I'll see tomorrow.

Kevin


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## g_axelsson (Nov 29, 2014)

Yes, crushing to a fine powder has been done but that doesn't mean there is gold inside the ceramics. Several people have tested it and come to the conclusion that there is no gold inside the purple ceramic body, the conductors consists of molybdenum that is plated only where exposed.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=52&t=12845&p=130916#p130916

Crushing the ceramic gives the acid easier access to gold braze under the die but crushing too fine and filtering will be problematic. It will be harder to wash out the gold chloride at the end. How far you want to crush is a personal choice.

Göran


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## pu_239 (Nov 29, 2014)

igi900 said:


> hi everybody I hope somebody will be able to help me I processed my gold with aqua regia .
> to be exact I used 10 Pentium Pro CPUs.
> which should give me 10 grams of gold at the end of the process because I read somewhere that each Pentium pro CPU as one gram of gold.
> after all the process was done I drop the gold with SMB the gold was dropped and dried and I had about 3 grams can anybody tell me if I'm losing gold during my process.my process was as follows
> ...



I have never done a gold recovery process yet, I will do one this week, my first one. But I am a chemist. I agree, with most post, it's just common sense. Don't believe the yield online. 

When you poured the solution out of the coffee pot, make sure you rinse the coffee pot as well with water and pour it in to the beaker, the one you had ice in. 
2nd, why did you add ice? I see no purpose, it's actually not beneficially, it's actually more harmful. Just because you believed the aqua regia stopped reacting with the gold, doesn't mean it did stop. There are still some reactions with gold going on that can't be seen with the naked eye. I would boil for 5-10mins after it appears there is no reaction. Don't use silver sulfate. Use something cheaper, like sodium sulfate. 

I would also drop the SMB in a hot solution of the gold complex, not cold. Hot solutions cause the atoms to move around faster, giving them a chance to find eachother faster and form bonds. Cold solutions have the opposite effect(this is why i wouldn't recommend the ice). Also make sure you wash your filter paper really good. Once you think you filtered out the gold complex solution. Put the funnel/filter paper in another beaker, add some water, test that solution for gold to make sure you got all of it out. 

I also seen people "adding water" this just dilutes the acid, giving it a longer time to react. This is also not beneficial. This idea i have(i am sure others have had the same), I believe it would be best to evaporate most of the water off after you add the SMB. this will help your gold recovery process faster. People say "leave it out over night." Just evaporate the water. Use something with a large surface area, like a pyrex baking dish. Pour the solution in there, rinise out the beaker in to this pyrex dish. Evaporating the water, will have multiple benefits. 1. It will reduce the volume, once again giving the molecules less room to move around, this will result in them crashing in to each other making bonds more quickly. It will also help with the recovery yield. The dish you put the gold complex and smb is the same exact dish that will have your dried gold. No need to transfer.


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## g_axelsson (Nov 29, 2014)

pu_239 said:


> I have never done a gold recovery process yet, I will do one this week, my first one. But I am a chemist. I agree, with most post, it's just common sense. Don't believe the yield online.
> 
> When you poured the solution out of the coffee pot, make sure you rinse the coffee pot as well with water and pour it in to the beaker, the one you had ice in.
> 2nd, why did you add ice? I see no purpose, it's actually not beneficially, it's actually more harmful. Just because you believed the aqua regia stopped reacting with the gold, doesn't mean it did stop. There are still some reactions with gold going on that can't be seen with the naked eye. I would boil for 5-10mins after it appears there is no reaction. Don't use silver sulfate. Use something cheaper, like sodium sulfate.
> ...


Cooling of the solution and adding sulfuric acid lets lead chloride precipitate as lead sulphate before filtering (Silver sulphate was probably a typo). Cooling and dilution of the gold chloride also makes silver chloride precipitate. Silver chloride is soluble to a certain degree in a highly concentrated chloride solution and can carry over trace amounts of silver to the final gold unless the solution is diluted. Most people don't work with so concentrated solutions anyway but it doesn't hurt so much when precipitating gold, it just takes longer time to settle.
When reducing a lot of gold chloride to gold it can also be a good thing to have ice in the solution as the reduction is an exothermic reaction.

"Leave it out over the night" is usually an advice given when people have dissolved gold with HCl and chlorine and it is to let the chlorine leave the solution so it doesn't affect the reduction with SMB.

I understand your enthusiasm pu_239, but before giving too much detailed advice about gold refining you might want to read Hokes book (available as download from the forum) and read some more of the postings by Gold Silver Pro and Harold V, two of our most experienced gold refiners on the board. Then you will get the finer details of refining.

Göran


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## Harold_V (Nov 30, 2014)

pu_239 said:


> 2nd, why did you add ice? I see no purpose, it's actually not beneficially, it's actually more harmful.


Depends, but I can't see any reason why it would be harmful. Chilling the solution, as well as diluting, will help precipitate those nasty traces of silver that behave like gold and stay in solution. 

No, I can't explain why that is. I'm not a chemist, but I've refined thousands of ounces of gold in my many years. 



> Don't use silver sulfate. Use something cheaper, like sodium sulfate.


For what? Precipitation? 
Neither of them would be a good choice. Ferrous sulfate would, as would sodium metabisulfite. For me, the choice was SO2 from a cylinder.



> I would also drop the SMB in a hot solution of the gold complex, not cold.


Patience, grasshopper. It appears there is much you don't understand about the refining process.

When one precipitates gold with SO2, heat is liberated. For those who like to speak chemist talk, it's an exothermic reaction. 

That being said, you'll come to find that when your gold chloride exceeds a given temperature, it will no longer precipitate gold, even when there's a generous excess of SO2 present. 

When I was refining, I precipitated from concentrated solutions. In re-refining, I'd have about 18 ounces of gold in a liter of gold chloride. To that I'd add enough ice to fill a four liter cylinder (including the gold chloride). It was not uncommon for the solution to end up too hot for the last traces of gold to precipitate. I'd have to add a little more ice, at which time it came down almost instantly. 



> I also seen people "adding water" this just dilutes the acid, giving it a longer time to react. This is also not beneficial.


Uhhh---that's not true, nor is it a desirable way to process. 

Give this idea a go. 

Place 30 troy ounces of silver crystal in a four liter beaker. To that, add a liter of 68% nitric acid. Heat if you wish. Not much happens. Now add some distilled water, and tell me what happens. 

Want another example? 

You can boil concentrated sulfuric acid in a cast iron kettle. No problem. Introduce water and you dissolve the kettle. 



> I believe it would be best to evaporate most of the water off after you add the SMB.


There is no practical reason to do that, and it may be a reason for greater contamination in the recovered gold. 

Here's my logic. 

It is not exactly uncommon for gold chloride solutions to contain elements beyond gold. If you evaporate the solution, you'll concentrate the contaminants, resulting in more of them being entrapped in the gold. You are best served allowing the gold to settle, then decanting all that can be readily removed, while it's still dilute. 

My brother-in-law, a published author, is a chemistry professor in a mid-west university. I have a recollection of him telling me that while he had an education in chemistry, it was clear to him that I knew far more about the mechanics of gold refining than he did. For that reason I'd advise you to pay attention to the prescribed procedures that are endorsed on this board. For the most part, they have been tested with time, and are known to yield the desired results. 

I'm sure you'll find the book quite elementary, I strongly advise that you read Hoke's book. From it you'll get an idea of the mechanics of refining. You may understand the principles, now, but you appear to not understand how things work. 

Harold


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## nickvc (Nov 30, 2014)

As I and many senior members have said before me refining is as much an art as a science, we are blessed here having both practical chemists and exacting refiners and in many cases both. Having a good knowledge of general chemistry to start helps but the whole field of refining precious metals needs to be treated as a specific field with so much to learn and master that I doubt anyone knows it all.


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## kurtak (Nov 30, 2014)

testerman said:


> I just found this thread/reply below, so, crushing the pentium pro's has been done.:
> 
> *How much gold in pentium pro cpu chip*.
> 
> ...



yes there is gold inside of them (between the top & bottom lid) - you do not want to crush them down to a fine powder - if you do you are going to have a filtering problem - you just need to break them open so the acid can get into the space between the top & bottom lids --- there is no gold in the ceramic - just in the "space" between the lids

Edit ; opps - I see goran already mentioned the filter problem if crushed fine

Kurt


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## solar_plasma (Nov 30, 2014)

Harold_V wrote:


> Chilling the solution, as well as diluting, will help precipitate those nasty traces of silver that behave like gold and stay in solution.
> 
> No, I can't explain why that is. I'm not a chemist, but I've refined thousands of ounces of gold in my many years.



In fact, I always got headache from calculating solubility products, but I found a complete calculation for this case on the net:

http://www.chemieonline.de/forum/showthread.php?t=87370 (the last post, the formulas should be international understandable)

In short words: The silver chloride will form  [edit: under the right conditions]  a AgCl2-complex with any excess of chloride. The solubility product in relation to the equilibrium constant of the complex reaction defines how much Ag+ will stay dissolved.

at 1 mol/l of Cl- the maximum total concentration of Ag+ is 0,022 mol/l, which could be considered as 3,15 g AgCl per liter.
at 10 mol/l of Cl- the maximum total concentration of Ag+ is 0,22 mol/l, which could be considered as 31,5 AgCl per liter.

Probably there are other variables to be considered in the reality since there is more than just HCl and AgCl in our AR. Also the temperature plays a role, that isn't considered in this calculation..

Any corrections are appreciated.


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## kurtak (Nov 30, 2014)

pu_239

Before I became a member here about 4 years ago I knew "nothing" about chemistry - everything I now know about chemistry is the result of being a member of this forum (ether directly from info on the forum or as the result of research outside the forum inspired by being here on the forum

That being said let me also say that in the 4 years I have been a member of this forum I have seem many people come here that had an education in chemistry but knew nothing about refining PMs --- but because they had an education in chemistry - instead of listening to the advise of the members here with "YEARS" of experience in refining they became confrontational & argumentative - their stay here was short lived (that's not meant to be directed at you - just a bit of advise)

Refining is an art/science/chemistry all its own - meaning as much as you may have an education in chemistry when it comes to refining your chemistry educations is just beginning - you still have much to learn & its time to once again hit the books (this forum being one of those books)

I am sure that if I tried applying my refining chemistry knowledge to other chemistry situations that you are more familiar with you would be telling me the same thing - so I hope I have not offended you - I would not be offended if you told me I still had a lot to learn about chemistry outside the chemistry of refining

Kurt


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## Anonymous (Dec 1, 2014)

testerman said:


> I just found this thread/reply below, so, crushing the pentium pro's has been done.:
> 
> *How much gold in pentium pro cpu chip*.
> 
> ...


Well, the verdict is in. 

According to my own crushing of the Pentium Pro CPU's, and then putting the crushed material into a beaker of AR, and adding the correct amount of HCL+HNO3 + Heat, I can say for myself that there is no more gold inside of the ceramics of the Pentium Pro's. I tried it myself, so my findings are not related to what others say.

I still have about 5 lbs worth of ceramic cpu's that could be tested too. At least 1 lb of them to see the results.

What I read somewhere, I believe on this forum or from somewhere else, according to the information, once the AR starts to dissolve the metals, the acids will travel along the inside of the cpu's and dissolve out the gold, which includes all the wiring and connections. I believe I read it somewhere.

Nevertheless, add my information to your notes and you should be able to conclude if there are values or not inside of the Pentium Pro CPU's. From what I did already, the answer is "no". No gold inside.

Kevin


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## g_axelsson (Dec 1, 2014)

testerman said:


> What I read somewhere, I believe on this forum or from somewhere else, according to the information, once the AR starts to dissolve the metals, the acids will travel along the inside of the cpu's and dissolve out the gold, which includes all the wiring and connections. I believe I read it somewhere.


Wrong, there were no gold inside the ceramic since there were no gold inside the ceramic at the beginning. The wires inside the body are made of molybdenum.

Göran


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## Anonymous (Dec 1, 2014)

g_axelsson said:


> testerman said:
> 
> 
> > What I read somewhere, I believe on this forum or from somewhere else, according to the information, once the AR starts to dissolve the metals, the acids will travel along the inside of the cpu's and dissolve out the gold, which includes all the wiring and connections. I believe I read it somewhere.
> ...


If I'm wrong about what I READ, so be it. But what am I wrong about? If the information isn't correct, then I can see "being wrong" on my source. I never said is I know for a fact, I said I read somewhere, and even if the information is wrong, at least it can be corrected in the form to make it right. You can quote and do as instructed, and then someone can say to you "wrong".... although you've done it by instructions. My claims are from MY OWN experiments. So I'm not wrong in suggestion what another source said. The source may very well be wrong, but don't blurt out on me like I'm promoting misinformed/bad information. I'm revealing something I've read. The same as reading Hoke's book. You read it. And guess what?... You Applied It!

Whatever the inside are made of, I believe I made a point/experiment that there isn't any gold inside of them. That was and is my point. No gold inside of the ceramic Pentium Pro CPU's.

Kevin


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## g_axelsson (Dec 1, 2014)

testerman said:


> g_axelsson said:
> 
> 
> > testerman said:
> ...


Okay, that's fair. What you have read (or remembered as you don't know where you read it and didn't give a source) is wrong. There are no gold traces inside the ceramic.
The statement that you have read it or remembered that you have read it is true. Maybe I should have cut out the part of the quote where you wrote you had read it somewhere. I apologize if I offended you. Sometimes I miss the finer nuances of the English language since this isn't my first language.

This reminds me a lot of my mother, she always tells me to add "I think" to anything I say so no one could ever tell me I'm wrong. 8) 

Back to refining, there are a couple of strong argument that there is no gold inside the ceramic from the beginning.

If there were gold conductors and


> the acids will travel along the inside of the cpu's and dissolve out the gold


 it would take very long time. The acid would be exhausted and stop dissolving gold after a short wile inside the narrow hole. There is no flow in such a narrow channel and the only transport mechanism is diffusion which becomes slower he deeper you go.

If there were gold conductors you could probably see them in a microscope when breaking an IC. I haven't seen it when looking at broken IC:s

If


> the acids will travel along the inside of the cpu's and dissolve out the gold


 it would leave hollow channels where the ceramic would break when crushing it. It doesn't.

If


> the acids will travel along the inside of the cpu's and dissolve out the gold


 it would leave a very concentrated gold chloride inside the channel and that is impossible to wash out after the AR treatment. You would have found that gold when you crushed the ceramic base but you didn't.

Göran


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## NobleMetalWorks (Dec 9, 2014)

I have processed hundreds if not more Pentium Pros. My average is .33 grams per CPU. I remove the caps and process separately. Since the AR solutions are dirty, I use a BDG process to extract the Au, then Oxalic to precipitate. No double refining needed.

Scott


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## Barren Realms 007 (Dec 9, 2014)

NobleMetalWorks said:


> I have processed hundreds if not more Pentium Pros. My average is 3.3 grams per CPU. I remove the caps and process separately. Since the AR solutions are dirty, I use a BDG process to extract the Au, then Oxalic to precipitate. No double refining needed.
> 
> Scott




Don't you mean .33g ea?


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## g_axelsson (Dec 9, 2014)

Now we know who is spreading the rumors about great yield on PPros! :mrgreen: 

Göran


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## Anonymous (Dec 9, 2014)

Well maybe they should be processed as normal and THEN crush the ceramic and process it later and work out the total yield. Just a suggestion......


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## kurtak (Dec 10, 2014)

According to these guys there is 1 gram per pen pro cpu :arrow: http://www.ozcopper.com/computer-cpu-gold-yields/

its the third one down from top

Kurt


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## necromancer (Dec 10, 2014)

that list looks familiar, just edited a bit. with a bit of false information....

there is no contact information on that site, wonder why.


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## NobleMetalWorks (Dec 11, 2014)

Barren Realms 007 said:


> NobleMetalWorks said:
> 
> 
> > I have processed hundreds if not more Pentium Pros. My average is 3.3 grams per CPU. I remove the caps and process separately. Since the AR solutions are dirty, I use a BDG process to extract the Au, then Oxalic to precipitate. No double refining needed.
> ...



Yes, that is exactly what I meant. I went ahead and edited the post. Thanks for catching that.

Scott


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## NobleMetalWorks (Dec 11, 2014)

The rumor of 1 gram per PP CPU has been going around and around for years now. If you simply search for Pentium Pro posts on this forum, you will soon find that the actual yields of members who have processed them are almost all the same.

There are times I will get .34 and others .3. It depends on the chips, where they were made, what year, what model, etc.

The only way you are ever going to understand the actual yields is if you practice your craft, become very adept at processing CPUs, and then keep your own data reviewing it when you want to understand yields of material you are purchasing to process.

When it comes to gold, people who are selling gold bearing material always believe there is far more gold in the material than there actually is. This rings true in almost every case. Just look at the unrealistic prices Pentium Pros sell for on ebay. You will see exactly what I am saying.

Scott


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