i`ve put av small batch of pins and fingers in nitric and filtered the base metals out, i`m fixing for another round of nitric once i`ve washed the filter with water to get the residues back in with the original finger and pin batch. after this second nitric i`ll see if all the base metals are gone by adding a little nitric to see if it keep fuming and if it does i`ll just repeat the process until there is no base metals left, this is my first step
newby first step
- Thread starter callicom
- Start date
Help Support Gold Refining Forum:
Sounds good so far. I would recommend processing the fingers in Acid Peroxide - view the videos on Steve's site.
Processing the pins in Nitric is OK but will give you problems if you have solder on the pins.
I do a boil in HCl for pins and remove as much base metal as possible since HCl is MUCH cheaper than Nitric for me. Once nearly all of the base metal is gone I decant, add more HCl, then a few drops of Nitric at a time, using heat to make the Nitric work quickly. Once the reaction stops, add a few more drops of Nitric, repeating until all metal is dissolved.
This way you have a cleaner AR solution and have used much less Nitric. As you get better at judging the reaction you'll be able to avoid excess Nitric and won't have to neutralize much at all. I follow Harold's suggestion and use a small button to use up the remaining nitric (weigh it before and after) and then precipitate.
Keep reading and proceed cautiously - you're on the right path.
Processing the pins in Nitric is OK but will give you problems if you have solder on the pins.
I do a boil in HCl for pins and remove as much base metal as possible since HCl is MUCH cheaper than Nitric for me. Once nearly all of the base metal is gone I decant, add more HCl, then a few drops of Nitric at a time, using heat to make the Nitric work quickly. Once the reaction stops, add a few more drops of Nitric, repeating until all metal is dissolved.
This way you have a cleaner AR solution and have used much less Nitric. As you get better at judging the reaction you'll be able to avoid excess Nitric and won't have to neutralize much at all. I follow Harold's suggestion and use a small button to use up the remaining nitric (weigh it before and after) and then precipitate.
Keep reading and proceed cautiously - you're on the right path.
element47
Well-known member
http://www.goldrecovery.us
or, advanced search for "author", enter "lazersteve".....it's in his signature line.
or, advanced search for "author", enter "lazersteve".....it's in his signature line.
thanks for the link, i havent seen the video yet but i will, but for this fisrt step batch i ended up with a brown mud with gold flakes, some small bits of cb`s and what looks like white dust (maybe 10 percent after washing maybe a dozen times. i`m not sure if i`m ready for ar because of the white dust and bits of cb`s or if i could proceed . any advice :?:
Geo
Well-known member
you can use AP to dissolve base metals in your pins if you use a bubbler and this will save problems using hcl+chl to dissolve your gold.imo its better than nitric because of the cost issue but if you really want to be frugal just make a gold cell.you can re-use your chemicals over and over and if done right you come out with a cleaner, purer gold.if you go with the cell be sure your material is clean and oil free and most important, dry.
this is my first and i`d like to take it all the way to learn, what bug me is the white residue for now, in the future i will have to bring the cost down and will have to figure out these other processes you are mentioning, the white dust is it silver chloride and is it preventing me from moving on to ar :?:
eeTHr
Well-known member
You won't make silver chloride in your first step, if you only added nitric acid. Any silver will go into solution in nitric, it won't form a white powder.
You gold will be in metalic form, either floating or sunk to the bottom, or both.
If your nitric is home made, the white powder is probably residual salts from the nitric making process. If so, first let the sediment settle to the bottom, then decant the nitric solution, leaving the sediment with your gold in the original container. Then a simple water wash would dissolve the white salts out of the sediment---add water, let the sediment settle, decant the water, leaving the sediment with your gold, in the original container.
If you have plastic or circuit board pieces in the mix, they won't be dissolved when you dissolve your gold. That's good.
Your gold will dissolve into solution when you add HCl and either nitric or Clorox. After all your gold is dissolved, when you pour the pregnant AR solution through a filter into another container, the plastic pieces and any other unwanted stuff will just catch in the filter. Your AR solution will now have no particles in it.
Then be sure there is no more nitric or chlorine in the AR solution. Then test it with stannous chloride to get an idea of how much gold is in solution (black is most, then grey, dark purple, and light purple when it is very diluted).
And then proceed as usual to precipitate your gold.
Silver chloride will form if you have silver in nitric solution, and you add HCl. If your nitric is homemade it might have some chlorides in it, however, and could form a little silver chloride if there is any silver in your scrap (it doesn't sound like there should be). But if this is what it is, then the filtering, as described above, will keep it out of your final AR solution.
If someone recognizes what the white powder is, and it's other than what I mentioned, they can tell you more about it, and what to do if the resolution is different that I have described.
This is minimal information pertaining only to what you have described so far. When processing other types of scrap, there can be more variables, for which there is lots of info on this forum.
You gold will be in metalic form, either floating or sunk to the bottom, or both.
If your nitric is home made, the white powder is probably residual salts from the nitric making process. If so, first let the sediment settle to the bottom, then decant the nitric solution, leaving the sediment with your gold in the original container. Then a simple water wash would dissolve the white salts out of the sediment---add water, let the sediment settle, decant the water, leaving the sediment with your gold, in the original container.
If you have plastic or circuit board pieces in the mix, they won't be dissolved when you dissolve your gold. That's good.
Your gold will dissolve into solution when you add HCl and either nitric or Clorox. After all your gold is dissolved, when you pour the pregnant AR solution through a filter into another container, the plastic pieces and any other unwanted stuff will just catch in the filter. Your AR solution will now have no particles in it.
Then be sure there is no more nitric or chlorine in the AR solution. Then test it with stannous chloride to get an idea of how much gold is in solution (black is most, then grey, dark purple, and light purple when it is very diluted).
And then proceed as usual to precipitate your gold.
Silver chloride will form if you have silver in nitric solution, and you add HCl. If your nitric is homemade it might have some chlorides in it, however, and could form a little silver chloride if there is any silver in your scrap (it doesn't sound like there should be). But if this is what it is, then the filtering, as described above, will keep it out of your final AR solution.
If someone recognizes what the white powder is, and it's other than what I mentioned, they can tell you more about it, and what to do if the resolution is different that I have described.
This is minimal information pertaining only to what you have described so far. When processing other types of scrap, there can be more variables, for which there is lots of info on this forum.
i put nitric over the pins and fingers about three times decanting the old nitric each time and putting new nitric then the fourth time the nitric didn;t do nothing and stayed clear so i decanted again and washed with water and decanted about a dozen times. it`s nice to look at, the flakes and the mud that i know is gold. the nitric is bought from a chemical supplier and not home made and in the dozen washes it didn`t disolve, do you think i should try nitric one more time for good measure :?:
callicom said:
I doubt it's silver chloride given your starting material....Id say store your powder somewhere safe.
I think you would be wise to do further research here on the forum and read C.M.Hoke and the forum handbooks available as a free download of several members signature lines ,Pattnor and Palladium been two that leap to mind.
I'm fairly certain many members can tell you how to proceed but it's fairly pointless if you don't understand what you have and why, if you do continue onto AR I think that the learning will be something you would rather not have had.....
eeTHr
Well-known member
callicom---
nickvc has the right idea.
If you just want to get your gold out of what you've got, you could put a match head amount of the white powder into a white plastic spoon, and put 3 drops of HCl in it, and see if it dissolves.
If it doesn't dissolve, add a drop of nitric to it, and see what happens.
If it doesn't dissolve in either, HCL, or the AR you made by adding the drop of nitric, then you can dissolve your gold with AR and then filter the AR into another container to eliminate the white powder along with the rest of the sediment.
On the other hand, if it does dissolve in the HCl, then it will dissolve in AR. And if it dissolves after you add the drop of nitric, same thing. In either of these cases, having it dissolved in the AR may cause problems in precipitation of your gold.
Maybe someone else on here knows what it would be, if you report back with your results of the spoon and drops test.
nickvc has the right idea.
If you just want to get your gold out of what you've got, you could put a match head amount of the white powder into a white plastic spoon, and put 3 drops of HCl in it, and see if it dissolves.
If it doesn't dissolve, add a drop of nitric to it, and see what happens.
If it doesn't dissolve in either, HCL, or the AR you made by adding the drop of nitric, then you can dissolve your gold with AR and then filter the AR into another container to eliminate the white powder along with the rest of the sediment.
On the other hand, if it does dissolve in the HCl, then it will dissolve in AR. And if it dissolves after you add the drop of nitric, same thing. In either of these cases, having it dissolved in the AR may cause problems in precipitation of your gold.
Maybe someone else on here knows what it would be, if you report back with your results of the spoon and drops test.
Geo
Well-known member
if your pins had any solder you have made a white powder called lead (II) nitrate.its just lead dissolved in nitric acid,its water soluble and can be removed by a hot water bath.and i don't think your brown mud is gold,it may have some gold stuck in it but for gold to precipitate out into a mud it first has to be dissolved and nitric alone will not dissolve gold.
i`ve ordered hoke`s book and meanwhile i`m reading the pdf hoke`s and he say`s in the book that the pure gold wont disolve in nitric but the lower karot gold will end up as a mud in the bottom on page 43. now thanks to you guys i`ll try the white spoon to see and then the hot water bath. i know i`m not at the melting yet but i have acetaline and oxigen bottles but i only have a cutting torch and brazing tip i wonder if this would work :?: thanks for the help, this forum is a blessing
Barren Realms 007
In Remembrance
callicom said:
Yes you can use your brazing tip set on low pressure so you don't blow your gold out of your melting dish.
thanks for the acetaline oxy info. as for the lead nitrate it seams like geo is right, i havent tested yet but i looked at the pin and 30 percent seem to have minuscule amount of solder from triming too close to the board :!: so i`ll start by giving it a hot water bath, i`ll give the results, thanks
well the hot water bath i gave it consisted of boiling water on the stove, pouring it over and decanting several times since i don`t have a hot plate yet. it has gotten rid of a large part of the white dust but what is left (3-5 percent of mud) is more like a very very light green. i poored just a smidgen of nitric over it and i let sit for half an hour and washed and decanted a few more times but this small amount is still there . is it possible that my ferrous well water i wash with causes this very very light green dust :?:
now i`ve taken a little hydrochloric and put a few drops on a small sample and it seams to disolve the white light green dust right out and leave only the gold (under magnifying glass) would it be a problem to have a final wash with hydrochloric, hydrochloric doesn`t melt the gold by itself from what i understand.
Since you started this process initially using nitric there is a good chance you have a small amount of it left with your gold. If you add HCl to it you will make AR, the strength of which will depend upon how much nitric was left. Rinsing alone will not remove it.
One solution to your problem is to incinerate, to red heat, your mixture of solids to kill off whatever nitric may remain. Dissolve what's left in HCl, Let settle, decant the liquid. Your gold should reamain untouched.
You can then twice-refine your gold to achieve the purity you desire.
One solution to your problem is to incinerate, to red heat, your mixture of solids to kill off whatever nitric may remain. Dissolve what's left in HCl, Let settle, decant the liquid. Your gold should reamain untouched.
You can then twice-refine your gold to achieve the purity you desire.
martyn111
Well-known member
callicom said:
In keeping with the forums effort to use correct terminology, you do not melt gold or any other metal using acids, you are dissolving the metal.
