Not sure how gold precipitate looks like...

[hfywc]

hi all.

i tried a small batch of plated pins with AP, with HCL/Chlorox and precipitation with SMB in that order. being new i was careless and did not follow any measurements/ratios of the chemicals. not all the metals melted totally. but i got a nice yellow liquid that i was hoping to be AuCl.

anyway on the last part with dropping with SMB(i used stump out), nothing happened. knowing that i made a mistake somewhere, i kept the final liquid solution hoping that later on i would be able to remedy it. weeks passed, i noticed the bottom is turning brownish in color. i read somewhere in the forum that it could be that there is an excess of chlorine which prohibits the smb from reacting with AuCl. so i applied heat...eventually this brownish color turned into brown mud which is very fine in nature and easily disturbed when you rotate the container even lightly.

the problem is that i don't know for sure if this brown mud is gold or not for i have not seen an actual gold precipitate....please help.

thanks,
alan

 

[jimdoc]

It is probably gold.Do you have stannous to test?

Jim

 

[qst42know]

To late for stannous, unless you redissolve a bit and test.

 

[philddreamer]

Hi Alan!
In the photo I was doing the final rinsing w/water. The color can be lighter or darker, depends on purity.

Like Jim said, did you test with stannous, to find out if any gold is still in solution? Do you know how to make stannous test solution?

Phil

 

[glorycloud]

I imagine that your gold precipitate might look more black than brown.
After a few washings with HCL and then water the color gets nice
and light brown like you see in phil's picture.

 

[hfywc]

maybe i could download a picture or two for you guys to look at hmmmm.....

also i'm not sure about the stannous cholride i made whether it's effective or not...i diluted some solder which says 60/40 in some hcl. i heated the hcl until it started to boil and then stop and let it continue it's course. it left some black powder at the bottom. later on i added some tin sinkers which i ordered online to increase potency...

i made three tests on the hcl/clorox solution--two before adding extra tin sinkers and once after. color i got was light brown...

i just found out that the solder i used contains lead... is that acceptable?

also very important!!!! thank you guys for pitching in...

 

[hfywc]

Hi Alan!
In the photo I was doing the final rinsing w/water. The color can be lighter or darker, depends on purity.

Like Jim said, did you test with stannous, to find out if any gold is still in solution? Do you know how to make stannous test solution?

Phil

is it heavy? does it settle quickly upon agitation?

 

[philddreamer]

Some pic's would help.
60/40 no good. Radio Shack has 96%tin/4%silver, that works. Their will be a bit of sediment, it's the silver that doesn't dissolve in HCI. I use 15ml of HCI & 1.5in of the solder. Every couple of weeks I add a bit more solder to ensure its potency; pure tin sinkers are excellent. Lead is no good. And remember, always test your solution!

The cleaner the gold, the faster it sinks. Like glorycloud stated, your gold it's probably very dark, it means some metals were "dragged down" with the gold, especially copper.
Use Steve's washing instructions:
1.Let the gold powder settle to the bottom of the beaker over night.
2.Siphon or gently pour off the used SMB solution into an old milk jug labelled Used SMB. Save in your stock pot or properly dispose of.
3.The gold powder stays in the same beaker you precipitated it in.
4.Add just enough water to cover the gold powder and boil for 5 minutes.
5.Let settle and pour or siphon off the water into the stock pot.
6.Repeat three times.
7.Add just enough muriatic acid to cover the gold powder.
8.Boil for 5 minutes and pour or siphon off into the stock pot after testing with stannous. If gold is present keep in separate beaker to precipitate later.
9.Repeat until the acid is no longer discoloured by the process.
10.Repeat the water rinse as above.
11.If you suspect silver is present as a contamination, repeat the process with hot 3% household ammonium hydroxide (unscented- clear). Put these rinses in a separate container and add muriatic acid until no more white silver chloride precipitates. You have added enough HCl when there are no more white fumes coming out of the liquid. (Any karat, dental, CPU lid, or gold filled scrap will have silver as a contaminate.)
12.Finish up the rinses with three more hot water rinses. Put these rinses in with the ammonium hydroxide rinses.
13.Gently heat the beaker containing the gold powder while swirling the beaker. As the gold dries it will begin to clump and move around the beaker freely. Don't allow the gold to stick to the beaker.
14.When the gold is 100% dry it should be a nice light tan color, if not re-dissolve it and precipitate again with SMB. Repeating the above cleaning process after precipitation. Good clean gold settles very quickly when precipitated and clumps into nice balls when dried. No gold should be stuck to the beaker when you are done.
15.When completed transfer the gold to a properly prepared melting dish and melt into a button.
Steve

I use fiberglass filters & a funnel, it traps the very fine gold. I save the filters & later, when I have few, I process them with HCI/CI.

As the gold gets cleaner, it will settle faster.

I hope this helps.

Phil

 

[joem]

where do you get the fiberglass filters?
would a bunched up furnace filter work?

 

[philddreamer]

I got some @ Home-depot. Fireplace insulation, left over is what I've been using, it also works good. Just pull a piece, about the size of a cotton ball or so. Depending on how fine the gold is, you would compress the plug. I leave the plug a bit loose the first time around, then on the second I compress it more, that makes the solution run thru quicker each time. Paper will be dissolve, can get a bit messy & some even fall into the already filtered solution.

Check this post out in TECHNIQUES: Whatman glass filters for gold stripping cell?

 

[HAuCl4]

This deceptively simple filtering technique is amazingly effective, and economical, and I learned it right here from one of your picture posts phildreamer!.

 

[Anonymous]

4.Add just enough water to cover the gold powder and boil for 5 minutes.
7.Add just enough muriatic acid to cover the gold powder.
8.Boil for 5 minutes

I routinely add at least twice the volume in water or acid.Any less and you risk "popping" the gold up on the sides of your container when the solution boils.Years ago my beakers looked like they were lined with gold powder after I finished with them.

14.When the gold is 100% dry it should be a nice light tan color, if not re-dissolve it and precipitate again with SMB.

This one could cause you to be redissolving your gold for weeks.The color of precipitated gold varies dramatically.It can look as light as melted gold,or as dark as night.There have been many cases where the gold precipitates with what appears to be "gold flakes" in it.
A couple of good rules of thumb are,
Do it right the first time and there will be no question,
and the moderators' favorite phrase....."Garbage in,garbage out."

I use fiberglass filters

I have never used fiberglass filters,however it makes very good sense.
The fibers will not "absorb" your solution,and will not break down like tissue paper.I have some here and will be trying it soon.

EDITED

I got some @ Home-depot. Fireplace insulation

I like this idea better.This would work better as a "plug" than traditional fiberglass.

 

[philddreamer]

Thank you HAuCI4, but I can not take the honor. I learned it from Irons. I just worked on it 'til I had it work good for me & shared some pic's. Some one said: a pic speaks 1000 words, or something like that. :lol:

 

[philddreamer]

Hi Mic!
I had trouble with the poping when I first started, so I tried a couple of things. First I added more water. I think I just miss understood "cover the gold" with just to the top of the gold, when in reality I could fill the beaker. :roll: I also notice that if a swirl the water when it starts to pop, it helps spread the temp all thru the bottom of the beaker & the popping stops. I think parts of the bottom get hotter that others. I get much less popping now.

 

[Anonymous]

Very nice.I use a hot plate with a teflon coated pot on top.This helps distribute the heat and if I have an accidental tip over,I have a couple of minutes to pour it into another container.Also my primary beaker for washes is a 1000ml thick wall.It helps distribute the heat as well as give me enough volume to add plenty of extra liquid if needed.

 

[lazersteve]

Here's some of the previous discussions on filter plugs:

Filter Plug Threads

I feel the fiberglass filter plug is the best choice for filtering dirty gold powder from the sulfuric cell, but the Charmin plug is best for nearly all other applications of the plug filtering method.

Here's some reasons why:

1. The raw material for the Charmin plug is less expensive and more widely available ( not everyone has a Home Depot down the road).

2. The Charmin plug gets all of the fine particulate the first time through.

3. You can use a fresh plug each time and are not required to 'clean' your filter medium before it can be used again.

I never plug filter gold that has been precipitated from pregnant solutions, I always let the powder settle, then decant off the liquid. The only method of filtration that I would use for clean precipitated refined gold is vacuum filtration. Solution absorption is not a problem with Charmin plugs if you filter a few mL of water through the plug before and after use.

I have used Charmin filter plugs with a variety of acidic solutions and have never had one fail or dissolve. I currently use the decanting method of separating the gold powder from my sulfuric cell runs, but when I get my hands on the right fiberglass material I'll definitely give it a try.

I tested some pillow stuffing material I had left over from a Halloween costume with sulfuric acid and it failed with 10 seconds, so be certain you get the right stuff as all of the pillow fillings mentioned by Irons are not created equal. Lou also points out a few synthetic fibers to avoid somewhere in the old thread if I'm not mistaken.

All in all, use the material that works best your particular application. Don't get locked into a tunnel vision mindset that there is only one way. This is exactly how new methods like the fiberglass filter plug come to be. The two variations of the filter plug both have there place in the small scale refiners tool box.

Steve

 

[lazersteve]

14.When the gold is 100% dry it should be a nice light tan color, if not re-dissolve it and precipitate again with SMB.

This one could cause you to be redissolving your gold for weeks.The color of precipitated gold varies dramatically.It can look as light as melted gold,or as dark as night.There have been many cases where the gold precipitates with what appears to be "gold flakes" in it.

Sorry for the confusing terminology, I certainly hope no one got stuck in an endless refining loop due to my poor choice of words. I feel that the statement is accurate as it stands, but I also feel that the color of the precipitated gold depends on many more factors than purity alone.

I'll revise the post so that it does not leave the refiner stuck in limbo trying to obtain light tan gold powder.

Steve

 

[Anonymous]

hi everyone! i am new to the whole refining process. has anyone tried the "sub zero" process? i am feeling very ignorant to this method. the mud and rinsing is a mystery to me. i have never seen "mud" in any form except that of dirt. i have been very excited about learning as i go but it will help to have a better clue on what i am doing-looking for.
i want to thank all of you for asking the same questions that i was having run through my head! you have given me a lot to think about!
thank you!

 

[Barren Realms 007]

hi everyone! i am new to the whole refining process. has anyone tried the "sub zero" process? i am feeling very ignorant to this method. the mud and rinsing is a mystery to me. i have never seen "mud" in any form except that of dirt. i have been very excited about learning as i go but it will help to have a better clue on what i am doing-looking for.
i want to thank all of you for asking the same questions that i was having run through my head! you have given me a lot to think about!
thank you!

Hold off on using it and do some reading on the forum and get a copy of Hokes and start reading.

 

[Barren Realms 007]

It can take on many colors. 8)











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