2 SMB Drop Fails .... Clear to Black and stays black

[altermad]

I Think I may have screwed up somewhere. I followed Laser Steve's Cell and every thing went well. So I venture on my own and am unsure of my next step.
Jar 1 - I Had a 24 K coated ceramic vase and dissolved the gold off with HCl / Cl, Filtered and set on a hot plate over night.
Jar 2 - I used a acid peroxide with some clorox (Was trying to dissolve gold from cb fingers) It flaked the gold off nicely. I rinsed with distilled to achieve just foils and wires. I then added HCL & Cl gold dissolved, I filtered again and let sit on hot plate for 2 hours.

I added SMB mixed with H20 to both containers they turned from yellow to a lighter yellow. ... Then I screwed made the mistake of stirring both with a cheap screw driver and both instantly turned black / brown but the solution doesn't seem to be settling. Any suggestions would be much appreciated! Also thanks to the folks that run and maintain this site. I feels great to learn then have a lab

 

[butcher]

The iron and dirt did not help, filter solution (save filter).
Use the screw drive for the intended purpose not as a lab stir stick.

Since you said you let this solution sit on a hot plate for two hours, I suspect you drove off the excess chlorine as gas.

But you may have also concentrate the solutions to salts, and you also may not have enough water in solution for SMB to make SO2 gas and precipitate gold, you may need to add water, I would double volume, let sit overnight, test solution in the morning with stannous chloride, you may also see brown gold powder had settled overnight, if the stannous test shows a positive (violet color), add a little more SMB and stir briskly, let it sit again and retest solution, when gold has settled and stannous shows negative decant the solution, wash the gold as Harold explains in the post (getting gold pure and shining, found in the help needed section).

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=49&t=325

 

[altermad]

Thanks for the advice. I will attempt these suggestions here in a couple of hours. Again thanks!

 

[Harold_V]

Thanks for the advice. I will attempt these suggestions here in a couple of hours. Again thanks!

A couple things for you to ponder.
I read that you stripped a gold plated ceramic vase. Is that correct?
I did not read that you tested the solution with stannous chloride after you stirred with a metallic screwdriver (which is NOT acceptable, not for any reason). Is that correct?

If I have it right, here's my take on things.

You stripped an almost imperceptible amount of gold. So little, in fact, that it likely has all been cemented by contact with the screwdriver. That would explain the dark color. You have created miniscule particles of gold, likely bordering on being colloidal, if not being so. They can stay suspended for days on end, and may never settle.

From this experience, I hope you learn that you can not strip a single item and expect a measurable recovery, and that you can not introduce metals to solutions without altering them in ways that are not in your best interest. It's obvious, from what you reported, that you don't have a clue what you're doing (no, I'm not trying to be rude) and that you have a serious need to stop doing what you're doing and to study Hoke's book, so you'll gain a basic understanding of how and why these procedures work as they do.

I may be able to suggest a way for you to recover the small amount of gold you have right now, but it's more important for me to understand how much you know than it is for me to provide guidance when it may not mean anything to you. If you can assure me that you know what you're doing, well get on with recovering that small amount of gold.

The ball is in your court.

Harold

 

[altermad]

Harold, Thanks for the response! Any you are right, I have never actually done this just read and read. The vase was guilded with 24k gold and I had broken it several months ago tried to melt the gold, used HCL and sodium nitrate to try to recover, after it tested 24k just never could come up with a way to recover it ... till I poured a little HCL / CL over it. Honestly I am glad to have that bag of broken ceramic gone.

I attempted to make the stanious with HCL , a 2" piece of solder and some heat but never could get a reaction. I poured some of the dark solution in the little I made and it just turned gray.
The Screwdriver was an idiot move... I learned what not to do
I think you are on the money with the miniature particles and them not settling. I am thinking a little Clorox was still left in the mix and no ice durring the precip along with the screwdriver might have created the little particles.

Update.... I combined Jars and I diluted and filtered the solution, I had a little bit settle after 10 hours, but most is / was suspended in the solution.

I took half of a shot glass of the brown water/hcl and added some clorox and walla back to the golden color, no particles all liquid. I am going to check in a couple of hours to see if the bleach is out and for curiosity sakes see if the SMB that was in the solution dropped material out. (I am guessing the SMB was or has been gassed out of it.) I plan on giving it another day before trying to precip it again.

"It's obvious, from what you reported, that you don't have a clue what you're doing" - The stripping cell worked great (Thanks to yours, Steve's and other members advice). Pretty sure I just took a wrong turn. I have read but there comes a point where a guy has to try and learn. I will certainly have a bigger batch for the ceramic next time ( I was more excited I figured out a way to strip it).

Thanks for your time and knowledge,

 

[Harold_V]

It's obvious you have read, and that you have an understanding. I stand corrected. I saw evidence of that when you had enough wisdom to try to re-dissolve the material, which is what I would have recommended.

Be certain you filter the solution prior to your attempt to precipitate again, and, if it's VERY dilute, so you'll have a better reaction, you might consider evaporating so you have a much smaller volume. It won't make a difference as far as the recovery percentage (unless you evaporate too fast and lose gold), but it may precipitate in larger particles and be more visible.

And, as a reminder---NEVER use metallic tools in solutions. That's what glass rods are for.

Make sure you tell us how it turns out.

Harold

 

[altermad]

Thanks for all of the help on this matter. I ended up adding CL back into the Brown water and it immediately turned back to the golden liquid. I split the batch for testing into 2. I then took batch 1 and heated on a hotplate for about 4 hours to drive CL out, dilutes 3x over then added some SMB and stirred with plastic. Batch 2 set in the shop window for 24 hours catching some sun, I then added some SMB and stirred with my new plastic rod.

Batch 1 had a very small amount of gold that fell out.
Batch 2 had a fair amount of gold fall out. 3x as much as the other half of the batch.

Not sure why the difference, but it seems to me that using hotplate to drive out the Cl reduces yields... am I boiling the gold off? 3 times I split batches and the hotplate batch always comes out with less gold than the 24 hour in the window batch.

Is this what you meant about "(unless you evaporate too fast and lose gold)"... I am learning every day and now a guy that could never afford to buy pure gold has about 2 grams (Guess looking through 24k jar with liquid still) of the brown powder. I would really like to thank you Harold for being willing to help a guy, I can't tell you how much respect I have for you, your knowledge as well as the fellow members.

Now that I have de plating down, my next step is to practice how to refine and recover with gold filled

 

[dtectr]

Harold -
Might there be a thin layer of gold cemented on the screwdriver?

 

[gold4mike]

When you use the hotplate to drive off the excess chlorine you want to keep it below boiling. Each bubble that bursts at the surface is a chance for some of your gold to be lost.

Heat it until you can see some steam rising from the surface and maintain that for awhile.

 

[Harold_V]

Harold -
Might there be a thin layer of gold cemented on the screwdriver?

Most assuredly, although it may not look like gold.

Harold