SOLVED -I Need Help With Black Powder After Washing It Clean

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butcher said:
The green solution has a lot more copper mixed with your gold than I suspected.

Remember if you have free chlorine your gold will redissolve, which can create a problem of using too much SMB to try and precipitate the gold.

Use the stannous chloride test to determine when you have enough SMB and the gold has preciptated from solution.

The Picture after SMB looks to have undissolved salts, and the color is closer to what I would expect to see a gold solution without copper, I also see no green from copper in solution, if this is the same solution, it looks like you also precipitated the copper, things are not looking right here, you may have used way too much SMB.
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The golden solution in the picture above, I just took another stannous test, and the results are exactly the same as the first picture. I can upload the picture of the q-tip, but it looks exactly like the other one in color. It's blackish/dark purple.

I know one thing for sure, and that is I didn't know what the exact ratio of HCL-CL to add for the amount of powder I was working with. Hopefully I didn't mess things up, but gold is still testing positive in the solution, which should mean that I haven't dropped all of the gold, if any, at all.

If it helps any, I didn't add any water at all to the solution.

Kevin
 
You could also be seeing a false positive test for gold, which will happen if you use way too much sodium metabisulfite.

The green color being gone from solution after using SMB is why I suspect this is the case, the gold should precipitate from solution before the copper.

The other thing, which may just be a remote possibility is you still have chlorine gas in solution, although I doubt this is the case if the stannous chloride is able to reduce the gold to give you the violet color in your test.

At this point I would take a stannous chloride test.
A trick I have used to test the color, if the color was very dark (almost black), is to hold the Qtip over a solution if HCl I was heating driving off oxidizers (nitric from aqua regia or bleach from HCl/NaClO), the steam from this solution will lighten the color on the Qtip that may look almost black and reveal the true purple color of the stannous test.

You may also try taking a few drops of liquid dilute it with water and retest it to get a lighter color to your Qtip to see if it is a brown or a purple (not a very dark color almost black, that is hard to tell if it is violet or brown or what).

You could also try heating the solution to see if gold will precipitate (this and using your stannous test).

And then there is cementing with copper this will cement gold if it is in solution, and will not hurt anything if it is not.

From the pictures and your description it just makes me think something went wrong.
 
Kevin,
I completely agree with butcher.

It seems that you may have used too much bleach at the start. And that much SMB I'm sure is way too much.

With HCL/CL the key is to add your bleach in very little amounts at a time. While continually stirring and waiting for the bleach to complete its task before adding more. I once dissolved nearly a Troy ounce of powder with HCL bleach in one jar. I looked at the formula in Hoke's book for AR to dissolve one ounce and because I was using bleach instead of nitric I knew that o would need about ( just a guess ) 15% more HCL because the bleach will mess with the pH. I then began to stir the solution and added bleach one cap full at a time, stirring and waiting about 15 min in between additions of bleach. If my memory serves me right, it only took like 3 or 4 cap fulls. Not much bleach at all.

Once all the gold was dissolved, I placed the container on an old coffee maker heater and let it sit there hot for a couple of hours. Then I let the solution cool to room temp and added a couple of hand fulls of ice. The ice will act to cool the solution as well as dilute it a bit. The cold gold chloride will not be able to hold any silver or lead if present and it will drop out as a white powder. Filter the cold solution into a clean beaker and its time to drop the gold.

You only need to use a bit more SMB than the expected weight of the gold to be dropped. So if you thought there may be 8 grams of gold, you shouldn't have to add more than 8-9 grams of SMB. Now if you still have chlorine in solution it could take a bit more SMB to get the gold to stay dropped.

Be patient with your solution after adding SMB. Because some times you get a nice fast drop or change in solution, but allot of times it can be quit slow and could even take several hours.

I hope that I was able to explain that clearly. I'm not as good with words as butcher is.
 
Your precipitate looks to be a mix of copper one chloride, miscellaneous salts, and gold. This happens when you have dissolved copper two chloride mixed with your dissolved gold solution and add too much SMB as mentioned above. The problem of CuCl mixed with gold powder is very easy to fix.

1) Filter out the solids.
2) Flush the solids with lots of hot water.
3) Treat the solids with an excess of full strength 31%+ HCl with lots of stirring. This dissolves the copper I chloride into the acid coloring it dark brown to black.
4) Allow to settle and decant or filter the solids out again, the solids contain your gold powder.
5) Incinerate to red heat if desired.
6) Dissolve the dirty gold powder again (straw yellow to orange solution this time ), filter until 100% transparent, and precipitate with the proper amount of SMB.
7) Left over solutions should all be gently heated until the smell of SO2 is gone, then tested for dissolved Au.


Steve
 
lazersteve said:
Your precipitate looks to be a mix of copper one chloride, miscellaneous salts, and gold. This happens when you have dissolved copper two chloride mixed with your dissolved gold solution and add too much SMB as mentioned above. The problem of CuCl mixed with gold powder is very easy to fix.

1) Filter out the solids.
2) Flush the solids with lots of hot water.
3) Treat the solids with an excess of full strength 31%+ HCl with lots of stirring. This dissolves the copper I chloride into the acid coloring it dark brown to black.
4) Allow to settle and decant or filter the solids out again, the solids contain your gold powder.
5) Incinerate to red heat if desired.
6) Dissolve the dirty gold powder again (straw yellow to orange solution this time ), filter until 100% transparent, and precipitate with the proper amount of SMB.
7) Left over solutions should all be gently heated until the smell of SO2 is gone, then tested for dissolved Au.


Steve
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First of all, I want to thank all of you that have helped me out and have given me guidance. It was worth its weight in gold.

Steve, you're the man. WOW. I was feeling so down when I thought I screwed up my stuff, but when you said,
lazersteve said:
The problem of CuCl mixed with gold powder is very easy to fix.
Click to expand...
that there, gave me all the hope I was needing, and I'm thankful for it too.

I managed to follow your steps, along with the post here by kadriver in the thread: Recovering Black Powder from the Cell
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=52&t=7093&start=80

and have completed my tasks.

Yes, I have officially refined and have recovered gold from escrap. I will make a thread with the pictures of the gold button I've made, all thanks to this forum. I was too determined to let my hard work go to waste, and I wasn't going to give up either. I've been reading, studying, reading and studying like there was no tomorrow. I've gained so much information and knowledge from all of this, and more as I completed each step. Now I understand more than just last week.

There are also a few concerns that I have.....

1. When I thought I botched my gold, Butcher said that (I think, the last resort) to place a piece of copper in the solution and it may/should collect the gold. I've done that first, before reading Lazersteve's post. Now, the copper has black on it, and has what looks like mildew on it. Below is the photo.

copper-pipe-01.jpg

My question is, is there any gold on it? or should I scrape the copper pipe and process the scraping with the acid?

2. Because I thought, again, I was adding too much SMB to the solution, I kept testing it with the stannous and it keeps on testing positive. I added SMB, tested, added SMB, tested, on and on, yet it still tests positive for gold. So, to not mess this up, I simply filtered the solution and recovered the solids, and rinsed the filter till it turned from yellow to white.

My question is, since I've already recovered gold so far and separated it, should I add more SMB to the golden yellow solution that's left to see if more gold will drop? and should I heat it a bit if it's below 50F outside?

3. When I added SMB the first time I thought I messed up my solution, I'm sure gold did drop. Now, when I redid everything as Steve suggested, and reading the other thread I mention above, it appears that after I made the aqua regia and then added the 10 drops of sulfuric acid to the solution, more gold, or something dropped out. I also have pictures of the dropped substance, and comparing it side-by-side with my washed and dried gold powders, they appear to look alike, in color and texture. Picture below.

gold-powder-01.jpg

My question is, should I dissolve that powder and see what happens? or should I melt it and see what happens? and should I scrape the copper pipe and put it with the substance?

Once again, thanks for all the help and guidance. It really helped, and especially when I needed it. The weather has not been good here at all and it's gong to stay in the 40's this week and rain/snow is in the forecast. I simply couldn't do much outside these last few days to almost a week.

I'm still gazing at this gold button. It's very shiny too. :lol: I'll put that picture in the Gallery.


Kevin
 
Normally if cementing using a copper metal to replace values from an acid solution, it is best to use a clean flat thick piece of copper.

With pipe some gold may plate inside.
Pipe can be used but I would use a large diameter cut it long wise and flatten it out.

A thin copper can dissolve to the point where pieces of copper fall off into cemented values, copper pipe will also do this after it dissolves enough to get really thin, thick copper buss bars from old electrical panels work well.

At the end of cementing I would take an old tooth brush and clean off copper buss bar brushing powder into solution, re-hang bar to see if more values cement onto copper, clean buss bar again with brush rinse off with spray from a water bottle dry and store in a plastic bag for next time it is needed.

The black cemented out on the pipe or the cement is your values that were in solution.

Here you let the copper pipe dry, (which will also form some copper carbonates and oxides) I probably would not worry at this point about getting the little bit of value off the pipe at this point, (although you can by putting it back into an acidic solution and brushing it off as described above), I would just put it in a plastic bag and used it next time I needed it, getting the values from it then.
 
butcher said:
Normally if cementing using a copper metal to replace values from an acid solution, it is best to use a clean flat thick piece of copper.

With pipe some gold may plate inside.
Pipe can be used but I would use a large diameter cut it long wise and flatten it out.

A thin copper can dissolve to the point where pieces of copper fall off into cemented values, copper pipe will also do this after it dissolves enough to get really thin, thick copper buss bars from old electrical panels work well.

At the end of cementing I would take an old tooth brush and clean off copper buss bar brushing powder into solution, re-hang bar to see if more values cement onto copper, clean buss bar again with brush rinse off with spray from a water bottle dry and store in a plastic bag for next time it is needed.

The black cemented out on the pipe or the cement is your values that were in solution.

Here you let the copper pipe dry, (which will also form some copper carbonates and oxides) I probably would not worry at this point about getting the little bit of value off the pipe at this point, (although you can by putting it back into an acidic solution and brushing it off as described above), I would just put it in a plastic bag and used it next time I needed it, getting the values from it then.
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Thanks for the advise Butcher.

I'll put it in a bag for later usage. It was a brand new piece of pipe (3 ft) I cut to that size (approximately 6" long). I normally cut my pipe open and flatten it out, but my saw have been not so nice when I started cutting down the length of the pipe. I need a sturdy place to clamp my vise to hold it steady.

After I use more SMB on the solution I have left and once it tests negative, I'll reprocess that powder that I believe is gold. And speaking of that, the copper pipe is still the same length, with no signs of it being dissolved anywhere that was in the solution.

Thanks again for all your help.

Kevin
 
lazersteve said:
Kevin,

Here are some additional notes on using SMB and testing the resulting solution.

SMB Details

Great job on the clean up by the way!

Steve
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Thanks Steve. That link also answered some of the questions I had. I'm glad you posted that link. I can see where some things may have gone wrong the first time. For 1), temp here has not even been near room temp for quite some time (weeks maybe).

I bookmarked that thread too.



Kevin
 
I haven't worked with the powder I think may be gold, but I did add some more SMB to the solution I have and it did drop more gold. I can see it on the bottom of the beaker. Not big chunks like the first drop, but at least I can see a bunch of fine brown powder in there. I'll post an update once I finish that off and reprocess the other powder that I have.

I'll be glad when the weather starts getting warm here. It's bright and sunny as heck, but, it's probably around 30-something degrees outside right now.

Kevin
 

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