# 10.6g Au, my task for the morning



## Acid_Bath76 (Jul 26, 2011)

I was able to get this off my latest batch of Ceramic CPU's (i960's, Cyrix, motorolla, TI.. ). They started with a two day HCL wash. I would heat it for a couple hours, and then turn it off. Come back and heat it up for a couple hours. I never left it unattended while the heat was on. After two days, I filtered the solution. Washed in gently in distilled water, returned all solid particles back into the 5000mL beaker. Dissolved in AR. Instead of adding the Nitric right away, I heated the HCL up and added the Nitric in small increments. Once the reaction ceased, I stopped adding. After my first attempt, I've taken the advice here to heart. Evaporating the nitric off towards the end is a pain. As expensive as the stuff is, it saves money too. Anyhow, I used about 80mL less than what was called for in the recipe. liquid was separated from solids, and then the solids were sprayed down with distilled water to gather the last bit of AR. Total volume was heated on Medium for about an hour. The AR was allowed to cool overnight. The next morning I added SMB, stirred for about ten minutes, and noticed an immediate particulate forming. Filtered. Rinsed in distilled water. HCL wash. Incinerated. HCL wash. Rinsed in distilled water. Melted. It was beautiful! Anyhow, I've rambled enough.


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## gold4mike (Jul 26, 2011)

Very nice !!


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## Acid_Bath76 (Jul 26, 2011)

gold4mike said:


> Very nice !!


 THanks! Despite my best efforts to keep this as clean as possible, I still end up with small spots of discoloration. Any advice? The melting dish is prepped and cleaned, and then glazed with borax. I try and keep everything and anything out except for the gold powders. Still, I get little gray spots. There aren't too many, but it really bugs me.


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## Claudie (Jul 26, 2011)

Well done. :mrgreen: 
As for the spots, it could be Borax or maybe something coming off of the torch tip. Just some suggestions.


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## goldenchild (Jul 26, 2011)

Acid_Bath76 said:


> Despite my best efforts to keep this as clean as possible, I still end up with small spots of discoloration. Any advice?



Refine your powder one more time.


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## philddreamer (Jul 26, 2011)

If its Borax, just boil in 10% sulphuric solution & it will dissolve the borax. 
Or, like Mario suggested, refine again. Also, are you following the proper rinsing steps?


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## dtectr (Jul 26, 2011)

Acid_Bath76 said:


> I was able to get this off my latest batch of Ceramic CPU's (i960's, Cyrix, motorolla, TI.. ). They started with a two day HCL wash. I would heat it for a couple hours, and then turn it off. Come back and heat it up for a couple hours. I never left it unattended while the heat was on. After two days, I filtered the solution. Washed in gently in distilled water, returned all solid particles back into the 5000mL beaker. Dissolved in AR. Instead of adding the Nitric right away, I heated the HCL up and added the Nitric in small increments. Once the reaction ceased, I stopped adding. After my first attempt, I've taken the advice here to heart. Evaporating the nitric off towards the end is a pain. As expensive as the stuff is, it saves money too. Anyhow, I used about 80mL less than what was called for in the recipe. liquid was separated from solids, and then the solids were sprayed down with distilled water to gather the last bit of AR. Total volume was heated on Medium for about an hour. The AR was allowed to cool overnight. The next morning I added SMB, stirred for about ten minutes, and noticed an immediate particulate forming. Filtered. Rinsed in distilled water. HCL wash. Incinerated. HCL wash. Rinsed in distilled water. Melted. It was beautiful! Anyhow, I've rambled enough.


Just one thought - 
Did you test your solution with stannous? Just in case - hey, its YOUR gold, might as well make sure you have it all! 8) 
Great job (I _think_, with the blurry photo, its hard to tell  ) & Great attitude. We have the opportunity to study at the "feet of the Masters", so to speak. Its funny how many we get here that would rather cop an attitude & be _right_, rather than listen & be _rich_ (Maybe someday).
just my dos centavos.


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## nickvc (Jul 27, 2011)

One point leaps to mind, I see no mention of filtering your solution before you drop your gold...
It's worth the effort if you want to be sure your solution has no contaminants in it.
Well done all the same it's worth the wait to get that first button.


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## Photobacterium (Dec 2, 2011)

thank you for sharing your process !

I'm curious how much you need to clean up the CPU's to make this process work.

I have a lot of CPU's that are not pretty. various forms of thermal pastes & adhesives.

Normally, for a proper engineering task, I would clean everything up, try to "run a clean shop".

But I wonder if it's worth it. I could sit there with a single edge knife blade for an hour - but do the chemicals care ?

I just wonder how much it's wise to clean the CPU's etc. before adding the HCl.


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## gold4mike (Dec 7, 2011)

The grease will give you issues later on when trying to get powder or flakes to settle, and might have an impact on filtering too.

I find that most of the thermal paste and adhesive goes away when I heat the CPU's to remove the lids.


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## Acid_Bath76 (Dec 8, 2011)

I guess it all depends how much time you have on your hands, and where that time is best spent. If you're doing thirty pounds of ceramics, personally, I'm not going to spend a lot of time scraping heat sink goo off. You're right, heating them during the first couple leaches will remove most of that stuff from the mix. To date, it hasn't posed a problem. Now that I've said this, tomorrow I'll start running into issues.


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