# Aqua Regia vs DBG gold precipitates



## Noxx

Hello,
I've got a new digital camera and I can focus at literally 0cm so here are some close-up shots of precipitated gold coming from AR and DBG.
The gold coming from AR still needs an ammonia wash. It's habitually a lighter colour.


----------



## Rag and Bone

Drop dead gorgeous. (Drooling)


----------



## lazersteve

Noxx,

Very Nice, excellent work.

Steve


----------



## Shecker

I second that.

Randy in Gunnison


----------



## Noxx

Thanks guys


----------



## NuggetHuntingFool

Are both lots of the same approximate purity? I'm just curious, because that DBG sure leaves some nice looking flakes.


----------



## Noxx

I would tend to say that the DBG gives better purity since it is highly selective by itself for gold chloride. Also, Oxalic acid is used to precipitate which is also highly selective for gold. Then I performed a one stage scrubbing.

This was only a test. I started with 7,90 grams. Losses were under 2%.

As soon as I will get a good vacuum, I will try to reach 99.999 purity. (According to the patent)

It seems to me that good filtration is the key. I will use 2.5 micron filter paper.

I only used a coffee filter for the last batch so it doesn't retain small particles. My DBG solution was not clear at some stages of the process thus indicating some contamination (white clouds, unsure what is it).


----------



## goldsilverpro

Try some glass fiber paper. High dollar but it sure works well.


----------



## Lou

Dibutyl carbitol is a great thing for consistent reliable 4N+ gold. Diethyl ether will also work much the same way and it smells better. At the same time it's extremely flammable, and in concentration, a narcotic.

I always filter through a quartz frit with an ashless filter paper put on it. If you're not concerned about throughput, but want to get all of the material (i.e. rhodium black) then I recommend a PTFE millipore filter.


Lou


----------



## Absolutsecurity

Wow thats pretty clean looking!!!!!!!! :shock: :shock: 

I LIKE !!
 
Glynn


----------



## Noxx

More gold precipitated from DBC.

6 grams.


----------



## Absolutsecurity

WWWOOOOWWWWW!! Noxx

Thats has to be the cleanest looking stuff!!

BRAVO!

Glynn


----------



## Harold_V

Noxx,

My experience led me to believe that you can judge the quality of your gold by the color. Rarely did I ever precipitate dark powder that wasn't well contaminated. The gold I refined a second time ALWAYS came down very light in color, much like that which you just showed in the two large downloads. 

My hat is off to you. Very nice!

Harold


----------



## lazersteve

Noxx,

Excellent color on the gold.


What precipitant are you using now?

How long is the precipitation taking?

Awesome gold.

Steve


----------



## Noxx

Thanks guys.

I'm using oxalic acid (hot, around 100C).

This precipitate came from an uneffective precipitation (about only 40% of total gold have precipitated)


----------



## lazersteve

Noxx,

Have you tried potassium or sodium oxalate? 

I had much better luck when using the oxalate salt (I used Potassium Oxalate made from Potassium Hydroxide (50% solution) and dry Oxalic Acid ).

Steve


----------



## Platdigger

Is 8$ a pound a good price for oxalic Acid?
Randy


----------



## lazersteve

Randy,

I bought few pounds of it about two years ago and I can't recall the price.

I'll do some checking for you.

Steve


----------



## lazersteve

Randy,

I paid $5.50 per pound for mine from skylighter.com

Steve


----------



## Noxx

Steve, I never tried Sodium Oxalate, maybe I could get better results. 

The problem is, Sodium Oxalate is more expensive than oxalic acid (well...here).


----------



## lazersteve

Noxx,

You can make your own sodium oxalate with sodium hydroxide and your dry oxalic acid powder dissolved in water.

Remember to make a salt just mix an acid with a base.

2 NaOH + H2C2O4--> Na2C2O4 +2H2O

Steve


----------



## oldtimmer

Interesting reading here. From what I can read, it appears as if Oxalic Acid will work better than SMB. Is this true? Sounds like it will produce a better quality of gold than SMB. Will it work if you are using HCl+Cl as opposed to AR?

Also I see the mention of DGB. What does the DGB stand for and is it useable or recommended for a someone new to use? 

I am still not able to get a nice light brown gold powder after 2x process with HCl+Cl. Mine is still coming out a dirty brown. As such I have not melted it down until I can get a better color. I am doing a HCL followed by water rinse two times after the gold is dropped. I currently have around 7.5 grams of gold powder ready to melt. Perhaps a Nitric Acid rinse once to remove any base metals that the HCl will not disolve?

Second question, is using AP to disolve the pins from the ceramic CPUs. It does not seem to want to disolve the iron pins. I have a batch in AP for three days now, and have not seen the pins disolved from under the gold plating. All I can see is that the gold plating is getting discolored and none is floating free. Should I swithc to Nitric Acid to disolve the pins from the CPUs?


----------



## nicknitro

Noxx,

I am so jealous. LOL

Very nice agglomeration as well.


:shock: 

Nick


----------



## Harold_V

oldtimmer said:


> Perhaps a Nitric Acid rinse once to remove any base metals that the HCl will not disolve?-


I have strong negative feelings about that idea. Not that it doesn't work, but more so that it can lead to dissolving your gold, or part of it. Sort of defeats the purpose. 

In spite of good rinsing, I think you'll find that your gold, especially if it starts to agglomerate and form large clumps, will retain some HCl, even after being well rinsed. 

I washed and dried gold with HCl for years-----and never failed to have HCl fumes come off my rinsed gold powder. That is not to say you can't avoid the traces, but unless you do, you're asking for problems. 

If you are refining your gold a second time, if the barren solution you have from the operation is relatively free of color, it is doubtful you have dirty gold. How you precipitate will effect the color, so you may simply be using a procedure that encourages a dark precipitate. I used SO2 gas, which readily precipitates a light color (I call it blonde) powder. Only when I precipitated from dirty solutions did I have a problem with unclean gold. 

Before you jump to conclusions that may be unfounded, why don't you try melting your gold to see how it turns out? I recommend a melting dish that is properly seasoned by preheating slowly, then raising the temperature to a red heat. Sprinkle enough borax on the dish to create a full thin coat. Melt your gold in that dish, using no more borax. If the gold melts and flows together without issues, and it cools without forming a noticeable surface scum (discoloration, which is oxidized contamination), you're good to go. 

If you pursue this method, the moment the button freezes, remove it with a tweezers. Don't allow the flux to solidify, otherwise you can remove the button only by breaking the dish, or heating until the flux is fluid again. 

Your flux, after melting your gold, should remain clear of color----the only exception being if you see a pink to purple color in the flux, which is colloidal gold. If you have a darkening of the flux, your gold is not pure. As little as you have, it wouldn't be hard to smash it thin for re-dissolving should it need a third refining. 

How about a report on the results?

Harold


----------



## yvonbug

Is 20 mule team borax laundry booster OK to use?


----------



## Noxx

Yes, absolutely.


----------

