Just Finished my FIRST ever GOLD BAR 1.025 Troy Ounce

[kadriver]

I am exhausted. I worked all last night and most of this evening to get my first gold bar. Amazingly it weighs just over 1 troy ounce (1.025 ozt). I could'nt believe it when I put it on my scale (I said a prayer before I melted and poured).

I became interested in refining a little less than a month ago. I assembled a considerable refining lab in the garage of a vacant property we own.

I used 49 grams of karat 14k gold with a touch of 18k and 10k.

I sell scrap gold, and get a good price for it.

I was scared to death that I was going to mess this up and destroy the gold somehow.

Tonight I am my wife's hero (this bar will pay for my lab). I am also a very satisfied and thankful new refiner - you never forget the first one.

Thanks for looking.

 

[skeeter629]

Awesome job! You should be very proud.

 

[joem]

Great job.

 

[Anonymous]

you never forget the first one.

Wanna bet? You didn't see how small my first one was.
Congrats,that is some beautiful gold bud.

 

[HAuCl4]

8)

 

[butcher]

nothing like the wieght of that shinning yellow metal in a pretty ladies hand to make her accept your new hobbie, great job.

 

[lazersteve]

Excellent bar with nice color! Great job.

Remember that there is always room for improvement.

Steve

 

[kadriver]

Here is a better picture of the bar

 

[Barren Realms 007]

That color is very nice. 8)

 

[Dave English]

That's beautiful. The large photo is going to give me gold fevor all over again! Great job.

 

[Harold_V]

Here is a better picture of the bar

Very nice, and I hope you don't mind some constructive discussion. Please understand that I am not trying to diminish your accomplishment, but to enhance your future results.

Note the surface of the bar----where it has a rose color, but not consistently. Sort of a coarse speckled covering. That's oxidized base metals of some description. Your gold needed further attention, depending on your objective. It most likely is not up to industry standard of 9995.

When you melt gold, if it's pure, it remains clear and shiny. When it's contaminated, notice that there's a film on the molten gold that constantly moves from the center of the molten mass to the edges. That's the base metal oxides being absorbed by the flux at the edge of the molten mass. You can cover the mass with flux, which will eliminate the coating, but it doesn't eliminate the contamination. You can also sprinkle a covering of borax on a button the moment it solidifies, which will also remove the oxide coating, but it won't improve the quality of the gold. If it is re-melted, the oxide still exists.

I found, through the years, that eliminating the condition we're discussing was quite difficult with a single refining, even when good and proper washing procedures were employed. I finally succumbed to refining a second time, which improved the quality immeasurably.

Having said my piece, if your purpose is to recover and sell to a buyer that resells to a refiner, it likely makes no difference, but if you end up with the opportunity to sell to a consumer, your quality should be such that it does not yield problems for him/her. Not only does that create trust, but it also can lead to a customer in need of refining.

Nice job, overall!

Harold

 

[Oz]

I will add one thing to what Harold said. If you are selling to an end consumer as having fine gold it goes without saying that it must be .9995 fine. If it is a jeweler that is making up alloy for casting a new piece of jewelry, the number 1 thing you need to have removed from Karat gold scrap (other scrap as well) is lead. The jeweler can deal with most contaminates found in karat gold refining other than lead used in poor repairs or gold fill. The lead is very injurious to the gold as to workability.

If you are honest with a jeweler as to your gold product he may well work with you on purity as long as you keep the lead out with a touch of sulfuric before precipitation.

 

[kadriver]

I may take Harolds input and re-refine the bar.

In Hoke, there is a proceedure that removes lead.

It seemed rather lengthy, but appears worth it.

Hoke says to add sulfuric acid to the aqua regia and boil it down to syrup.

Then add hydrochloric. It says that this removes excess nitric acid

Plus it removes LEAD.

I will study this process some more and get everything strait.

Then I'll set up to refine the bar again to the proper purity.

Thank you for your help.

I welcome all criticism. I am very interested in getting it right on.

kadriver

 

[norcalmatt]

kadriver,
Thanks for the very informative and picture heavy posts. I am a little ways behind you and would like to say that
I really appreciate the posts you have started. I am new to this also and "Getting it RIGHT" is the best way and criticism
from these guys will only make the final product better. I look forward to reading more from you and hope to contribute a bit
as well. Keep those posts coming.
Matt

 

[Harold_V]

In Hoke, there is a proceedure that removes lead.

It seemed rather lengthy, but appears worth it.

Actually, the procedure is lengthy because of the nitric, not because of any lead that may be present. For those that evaporate instead of using urea, the only difference in time is the few seconds it takes to introduce a few drops of sulfuric to the solution. The addition of sulfuric causes any lead that may be present to precipitate as lead sulfate, which is then removed in filtration, prior to precipitation.

As Oz suggested, gold can be "contaminated" with various elements with relatively low harm (although that's not desirable), but even traces of lead destroy its ductility. It is said that molten gold can absorb fumes from lead being melted in the same environment. They have a strong affinity for one another. For the bench man, that spells death, for they can't set stones in gold so contaminated without breaking the prongs or burrs.

Regardless of the source of the gold I processed, every lot received a few drops of sulfuric, as insurance against lead that may have inadvertently slipped in to the process. You just never know.

Harold

 

[kadriver]

Please, let me make sure I have this right:

Once the gold is dissolved in aqua regia, then I add a few drops of sulfuric acid to the solution.

The sulfuric acid will precipitate any lead in the solution as lead sulfate which is filtered out at the first filtering.

Then proceed as before with the rest of the process....

This seems too easy to be true - but I will do it when I process the gold bar.

I actually read Hoke AFTER I had gottne to the sodium metabisulfite stage with the gold bar.

I did not roll the gold into thin sheet and then cut into small pieces.

I did not anneal the pieces first.

I did not treat with nitric acid.

On this next refinement I will make sure to include these pre-treatments, and make sure and add the sulfuric acid once the gold is dissolved in AR.

One question - is it true that lead sulfate will dissolve in hot water? If this is true, and one is not carefull, then it seems possible that the lead could end up back in the AR-Gold solution - does this sound correct?

Please give me all the criticism you can pile on - that is why I am here!

Thank you - kadrive

 

[Harold_V]

Please, let me make sure I have this right:

Once the gold is dissolved in aqua regia, then I add a few drops of sulfuric acid to the solution.

The sulfuric acid will precipitate any lead in the solution as lead sulfate which is filtered out at the first filtering.

Then proceed as before with the rest of the process....

Correct. However, considering you're processing karat gold, my recommendation is for you to inquart. It's one of the ways you can eliminate a huge amount of base metal, thus yielding somewhat cleaner gold.

I did not roll the gold into thin sheet and then cut into small pieces.

I did not anneal the pieces first.

I did not treat with nitric acid.

On this next refinement I will make sure to include these pre-treatments, and make sure and add the sulfuric acid once the gold is dissolved in AR.

Make it easy and just melt when inquarting, stir well with a graphite rod, then pour the inquarted material in a deep metallic vessel filled with water. You'll end up with what I like to call "corn flakes", which readily dissolve in dilute nitric. (When poured over the lip of a melting dish, you don't get shot.) Do not pour to a plastic container. It's not uncommon for the molten metal to form a steam cavity and hit the bottom still red hot. Need I say more?

One question - is it true that lead sulfate will dissolve in hot water?

No. Lead sulfate can be considered insoluble in water, hot or cold. It's lead NITRATE that is soluble in hot water.

Please give me all the criticism you can pile on - that is why I am here!

Not necessary. Wise people listen and appreciate helpful tips. You appear to be one of them.

While the "big boys" tend to process without inquartation, it can be the source of considerable frustration, particularly when you have the misfortune to experience an alloy that is abundant in silver. When the silver content is too high, the material often can't be dissolved in either nitric, or AR. Because the gold content is high, it protects the base metal from dissolution with nitric, and, again, because silver is high, the resulting silver chloride that forms when you attempt dissolution with AR, becomes a hard crust on the surface, isolating the metal from the acid.

Good luck with your next batch. I expect you'll do a great job.

Harold

 

[HAuCl4]

What irks you the most Harold?. Silver chloride or lead sulphate?. :lol:

 

[kadriver]

I will do the inquartation with this bar as well and pout into a METAL container filled with water.

I remember reading about inquartation in Hoke which says to use silver, clean copper, or clean brass.

I have some clean silver.

Is silver the best metal to use for the inquartation since I can recover it later?

Thank you again for all the input.

kadriver

 

[HAuCl4]

Silver is the recommended metal for inquartation because it requires the least amount of nitric acid and as you said, you can recover the metal later. If you are very careful and thorough and use the 3-1 ratio or more silver to gold, and at the end you boil the gold "mud" that is left in concentrated nitric acid for 15 minutes, and wash thoroughly afterwards, you can produce very fine gold 998-999+. In fact many people do just that and fluxing after.

Here's a great thread to read thoroughly from beginning to end:

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=50&t=1275&start=20&hilit=4metals+manganese+dioxide