dropping out gold

[patnor1011]

nice and shiny...

 

[EVO-AU]

Stihl88: I see you are from Australia. I know this has nothing to do with Au hunting, but are you by any chance a Melborne shuffler ? Phill

 

[stihl88]

Hi Phil, By Melbourne Shuffler do you mean "Dance style"? I had to look that one up on google... The only dance i ever did was on my wedding night.

 

[azdave35]

when using s02 gas does the gold drop as actual metal or sludge?

 

[jimdoc]

I will be a brown or tan powder as when using SMB. The SMB creates So2 gas.

 

[Harold_V]

when using s02 gas does the gold drop as actual metal or sludge?

Gold is precipitated as miniscule crystals. On rare occasion they grow large enough to be recognized as such.

Precipitated gold is not yellow because of the intricate surface, which reflects light in all directions. All that is required to align the gold and cause it to appear yellow is to abrade the surface. Something as simple as rubbing the gold powder with a porcelain spatula will cause it to turn shiny and yellow. That, of course, depends a great deal on the purity of the powder in question. If gold is precipitated from dirty solutions, the drag down tends to darken the powder, often causing it to come down very fine, so it doesn't agglomerate well.

Make no mistake----when you precipitate gold, it is in the metallic form. It does not readily form compounds, and those that are created can be extremely unstable, some even explosive in nature. It is for that reason that gold is typically found in the elemental state, although it may be alloyed with other elements.

Now what I need is for one of the chemists to correct my dissertation in areas where I have erred.

Harold

 

[Richard36]

Make no mistake----when you precipitate gold, it is in the metallic form. It does not readily form compounds,and those that are created can be extremely unstable, some even explosive in nature.

Now what I need is for one of the chemists to correct my dissertation in areas where I have erred.

Harold

Yeah buddy!

It is a fine line between refining, and creating metallic fulminates.

Fulminates can be created from several metals, Mercury, Gold, and Silver are the ones we need to be extremely carefull with.

For instance, if you have silver in a nitric solution, do not add it to a stock pot in which you have used solutions from platinum group tests containing Alcohol. This will create a metallic fulminate within solution.

If this solution is let evaporate untill dry, you will have a powerfull explosive compound that will explode with the least spark.

Fulminate of mercury is created in a similliar fashion, and is the compound found in Detonators, commonly called blasting caps.

Yeah, ... lets see you try to melt some of either of those two compounds with borax in a melting dish.

I want to be a couple of hundred yards away before you try.

Point being, be carefull, and know what you are doing, as well as why you are doing it, before you do it.
"High Speed Chemistry" can be leathal.

Toxic Fumes are the least of your concerns, if you do not know what the reaction will be, or the product produced.
Many, many, Alchemists met their end by doing such experiments.

Sincerely; Rick. a.k.a. "The Rock Man".

 

[azdave35]

someone on this thread said you can get smb..(sodium meta bisulfite) at kmart...where in kmart is this located?...what brand name is it?..how do i go about finding it?..thanks in advance

 

[geonorts]

I was advised by another member to try kmart however this was an Australian member advising me also an Australian member I don't know if kmart stocks it in other countries. It was in the home brew section its used as a sanitizer, its a small container 250gm i think with a bright orange label.

 

[obbarafun]

I ussually use smb for precipitate my gold , I read in the Hoke book use1 pound copperas for presipitate 50 dwt of Au , that convertion in grams is 5.8 grams of copperas for drop 1 gram of Au , but what you say in grams is .91 gram of copperas per gram of Au to recuperate , so that mean the quantive of copperas to use is small than if I use sbm , is that right?.
Also when I use smb the gold in black powder stick in the wall of the beaker , happen the same thing when use copperas?.
ALways we learn some new.Thanks.

 

[Harold_V]

I ussually use smb for precipitate my gold , I read in the Hoke book use1 pound copperas for presipitate 50 dwt of Au , that convertion in grams is 5.8 grams of copperas for drop 1 gram of Au , but what you say in grams is .91 gram of copperas per gram of Au to recuperate , so that mean the quantive of copperas to use is small than if I use sbm , is that right?.

Copperas (ferrous sulfate) will precipitate gold at a rate of one once for one ounce. A pound of copperas for 50 dwt of gold is way, way, way overkill. Please go back to Hoke and reread what you think you read. She advises a slight overage, which insures that you recover all of your gold, but it isn't required. If you test with stannous chloride immediately after introducing the copperas (solution, not as crystals), you will know if more is required. Assuming you have removed free nitrates, the reaction is instantaneous.

Also when I use smb the gold in black powder stick in the wall of the beaker , happen the same thing when use copperas?

What you described is fairly common, and is worse if you use plastic. I used to use a plastic policeman (see a chemical supply catalog) to remove the gold that adhered to the sides of my beakers, which worked quite well. It prevented scratching.

Avoid using glassware with scratches for precipitation. Gold adheres to the scratches quite readily, and can be difficult to remove.

Harold

 

[Richard36]

Hello Obbarafun,

I am not certain about the ammount of precipitant to recovered gold ratio,
But as for the question about what the precipitate looks like with Copperas, also known as ferrous sulfate,
The precipitate is brown, and sinks to the bottom of the dish.

Let the solution sit untill it is tottally clear of the brown haze within it created from the addition of ferrous sulfate.
Decant off the bulk of the solution, and filter the rest to recover the brown precipitate. Rinse the filtered material by spritzing the brown material in the filter with a solution consisting of 1prt HCL or 1 prt Nitric acid, and 1prt Water. This will dissolve the iron from within the precipitate, producing a cleaner product, which can be dried, then mixed 1 prt gold precipitate, 3prts Borax, 1 prt Sodium Nitrate, and melted to produce metallic gold.

I hope that this has been helpful.

Sincerely; Rick. "The Rock Man".

 

[Harold_V]

Rinse the filtered material by spritzing the brown material in the filter with a solution consisting of 1prt HCL or 1 prt Nitric acid, and 1prt Water. This will dissolve the iron from within the precipitate, producing a cleaner product, which can be dried, then mixed 1 prt gold precipitate, 3prts Borax, 1 prt Sodium Nitrate, and melted to produce metallic gold.

I strongly advise AGAINST the use of nitric. Remember, the gold is being precipitated from a chloride solution, so you risk re-dissolving some of the gold in the process specified.

There is a lot to be gained by washing precipitated gold properly. I have posted on the subject several times, and have an excellent track record of producing gold of outstanding quality. If your objective is gold of high quality, I suggest you explore the forum and read the comments in that regard.

Harold

 

[Richard36]

True, I got ahead of myself just a little.
Rinse the material in the filter with Water only first, Then with the acid water rinse second.

That way all traces of HCL will be removed if you should so choose to use Nitric with water to spritz your material in the filter. HCL and water works, but Nitric Acid and Water works better.

Harold is correct though, If using a Nitric/Water rinse, Be sure to rinse the filter material with disstilled water to remove all Chlorides before you do the rinse, lest Aqua Regia be formed, and some of your Gold be dissolved as the AR is formed, causing you to lose it into the filter rinse water.

I hope that this clarifies what I was trying to get said in my previous post.

Sincerely: Rick.

 

[Harold_V]

True, I got ahead of myself just a little.
Rinse the material in the filter with Water only first, Then with the acid water rinse second.

As I said, read the forum and learn how to wash gold properly.
If contaminants could be rinsed out that easily, everyone would be producing 4n's gold.

Harold

 

[obbarafun]

That formula that you use 1 pt nitric , 1 pt HCL and 1 pt H2O , look to my a combination of aqua regia and I think that remove Fe , but also have the risk of disolve the gold again , also I think that combination of melting pure gold use too much borax , but that's my opinion.
Thanks

 

[Harold_V]

That formula that you use 1 pt nitric , 1 pt HCL and 1 pt H2O , look to my a combination of aqua regia and I think that remove Fe , but also have the risk of disolve the gold again , also I think the combination of melting pure gold use too much borax , but that's my opinion.
Thanks

He didn't intend for the HCl and nitric to be used together, but one or the other, instead. You are quite correct that mixing those two acids in any proportion will make AR, which will, indeed, dissolve some of your gold.

I strongly suggest you disregard everything he has said. He obviously has no experience in washing refined gold, otherwise he wouldn't have instructed you to get the precipitated gold into a filter, or to spritz it with either of those solutions. It requires a prolonged boil to remove the contaminants, which do not leave easily.

I think you'll find that you can precipitate and wash your gold in the same beaker, and dry it there as well. There is absolutely no need to filter the recovered gold, not unless you have a huge volume. The only time I filtered my recovered gold was when I did the second refining, and then only because I had no less than 75 troy ounces to dry. It made more sense to use a Buchner to remove the water than to attempt to evaporate. By the way, gold that has been refined a second time and has been precipitated with SO2 comes down quite heavy, so virtually none of it sticks to the filter paper, very unlike dirty gold that has not been properly washed.

Assuming you do your work well, there is NO need for adding flux to your gold when melting. It will melt perfectly well in a flux covered dish. If you find it starts getting the least bit sticky, add a few granules of borax glass or anhydrous borax to the dish, on top the the current heat. It will readily clean the surface of the gold and move to the dish sides, creating a free flowing condition for your gold to be poured easily. In order to avoid pouring flux with your gold, never have excess in the dish. It serves no purpose unless you have done a lousy job of refining.

Harold

 

[obbarafun]

Also when I use smb the gold in black powder stick in the wall of the beaker , happen the same thing when use copperas?

What you described is fairly common, and is worse if you use plastic. I used to use a plastic policeman (see a chemical supply catalog) to remove the gold that adhered to the sides of my beakers, which worked quite well. It prevented scratching.

Avoid using glassware with scratches for precipitation. Gold adheres to the scratches quite readily, and can be difficult to remove.

Harold[/quote]
What I do to remove down the gold in the wall , in the washing process 50%HCL and 50% H2O , when is warn , I hold the beaker with two hand and move the liquid carefully and slowly around the wall and the gold go down really easy.
Thanks

 

[Oz]

First off I will defend Richard slightly as he has made no pretenses as to being a refiner but has claimed expertise in geology and assaying. In this post however he has given refining advice that should be corrected if needed. Proper assaying is very different from refining and I think the two have been confused in this thread a bit from the view of the novice.

When I first heard Harold advise against the use of nitric in this particular circumstance I was ready to reinforce what he has always said about changing acids (you long timers know what I mean). I waited for him to say it however instead of interrupting. I read what Richard wrote as either/or with nitric or HCl the same as Harold did. Nitric is a bad idea here.

Harold, I was amazed and astounded that you did not say it for the hundredth time, incineration. Richard although you will not have great losses if you wash your gold precipitate very well after being in HCl there will be some losses due to chlorides that are still present if you use nitric without first incinerating as Harold has always preached.

I can not help myself at this point but to give Harold a “oh my” in that he did not continue his preaching of the wisdom of incineration in this case as he has in the past.

Sure enough, I also understand that one tires of singing the same song when so few hear the music.

 

[Harold_V]

Harold, I was amazed and astounded that you did not say it for the hundredth time, incineration. Richard although you will not have great losses if you wash your gold precipitate very well after being in HCl there will be some losses due to chlorides that are still present if you use nitric without first incinerating as Harold has always preached.

I was trying to shift the emphasis away from nitric, not trying to make it viable, which I refuse to do. It isn't necessary, and solves no problems that can't be solved by alternate methods; methods that remove risk of loss of values. Further, in order to incinerate, the gold would have to be removed from the beaker. That makes no sense. Once gold has been precipitated, there is no good reason to remove it from its container until it is ready to be weighed (and/or melted) as a finished product.

When I talk of incineration, I'm not suggesting just warming things up---I mean it to the word. I never incinerated precipitated gold unless it was intended to be immediately re-dissolved, such as when wiping up a spill. The connotation "incinerate", in my mind, is to take the material to a dull red heat. That should not be accomplished in anything but metal unless a fused quartz dish is employed.

I am not lost on the fact that Richard knows a great deal about minerals, and, likely, assaying. I just want to insure that he sticks to that which is his field of expertise, and not lead readers astray. I had even gone so far as to suggest that he was confusing assaying procedures with refining procedures, but I changed my mind, not being sure that I was correct in my assumption. I did not post those comments, not wanting to say anything that would be misleading.

This I can say with certainty. First refined gold should always be boiled in HCl, rinsed well with water, washed with ammonium hydroxide, rinsed well with water, then boiled once again in HCl, followed by proper rinsing with water. Even that procedure won't yield exceptional quality, but it removes far more in the way of contaminants than a spritzing will remove.

My point is that readers should ignore the suggestion to wash their recovered gold in a Buchner, or gravity funnel. The only exception would be if they are not the least bit concerned with quality. There are those that have no interest in taking gold to a high state of purity. In that case, his advice is fine.

I can not help myself at this point but to give Harold a “oh my” in that he did not continue his preaching of the wisdom of incineration in this case as he has in the past.

Sure enough, I also understand that one tires of singing the same song when so few hear the music.

Heh! Incineration is one of the things that has been chiefly ignored by the masses. There is so much nonsense being promoted (not on this site) that no one understands the significance, nor do they wish to hear it. The vast majority of readers that have no experience will always take what, to them, is the easy way out. Dissolve your material in AR, precipitate, and, viola! You have gold ingots.

Well, you and I know that just isn't so, and until each reader experiences the problems that are associated with following foolish advice, there is no helping them. It has been my experience that in many cases, only after an individual has burned to the ground is he willing to listen to sound advice.

I have said my piece. It's like a horse to water. I can lead, but it is up to readers to absorb that which has been given freely. If they don't mind the problems that come from processing dirty materials when there is a better way, so be it. Maybe that's why I was successful in refining when so many were not. I used good sense. I read Hoke.

Harold