lead /nitric acid

[mountaineer]

Can someone tell me how nitric acid effects lead?

 

[Lou]

It dissolves it giving a colourless solution of lead (II) nitrate. If the nitric is exceedingly concentrated (as in 90%+), it doesn't dissolve, but rather forms a passivated layer of lead oxides (much like mercury does)

 

[Platdigger]

And then add a little sulfuric and........down she comes.
Randy

 

[mountaineer]

thankyou!

 

[goldsilverpro]

I usually use a 7 pts water/ 1 pt HNO3, hot, to dissolve lead

 

[Irons]

Heavy metal nitrates are something to be handled carefully. Even what seems like a minor spill can contaminate a large area.

 

[Anonymous]

Ok, well, I did my first merc burn and was too safe, with to much distance and too much wind and so, I could not see the puff of smoke, my fault....so, I over heated the gold, some lead melted adn coated the gold....I have applied nitric as directed by local miners, maybe twice for up to one hour....but, there is a dull, creamy coating on the gold...it is fine beach gold to some small pickers, maybe 1/8 in long....

I have read here to use sulfuric, but, don't have any....and have read that nitric, combined with ?chloride? in the soil can actually disolve fine gold?????

so, any ideas?

Lastly, i keep reading different methods...but what i have is nome beach gold....mined in an old dump area and there is lots of mercury and small lead {from batteries} in most of my gold...

so, should I get as much of the lead out....apply nitric...then burn the merc....

OR, apply the nitric and burn at the same time, which i have seen posted...

I would like to sale these two ounces tomorrow!!!! but i'll wait on some good advice....

 

[Blacktoadd]

If you have access to a furnace, it is common practice to add litharge to gold, (a form of lead oxide) to bring down the fine gold. Gold and lead like each other as you see. Then they fire it in a cuple which absorbs the lead from the gold. leaving shiny nugget behind. Discribed in assay of gold also. If you have other impurities the nugget will be dull. Re firing using fluxes will pull out other impurities. If you read Hoke she states it doesn't hurt to melt gold in open air repeatedly without harm to the gold. The impurities will come to the surface, oxidize off with waves of a tourch. The gold will eventually come out shining. try it with a little piece.
Bruce

 

[Anonymous]

i read that you can ad sulfuric acid to get the lead off? or do you add it to the nitric? Hot?

thanks!

 

[Harold_V]

i read that you can ad sulfuric acid to get the lead off? or do you add it to the nitric? Hot?

thanks!

Sulfuric acid is added to the gold chloride solution prior to filtration, which expels the lead as lead sulfate. It is then removed in filtration. A few drops of sulfuric will generally do the job unless you have been working with considerable solder.

Harold

 

[Anonymous]

ok, I was reading this post and not thinking of anything to do with filtration when I posted, just looking to clean up my gold that I melted the lead to, but, i've got that sold now.....

BUT, what i do need help with now is i was told by the dredgers here to clean my gold of my merc and lead, to just burn off the merc, quickly....then put nitric into the solution , it foams, it turns a different color...do it several times...it cleans up...put baking soda in fresh water, put into solution, rinse several times.....the lead is gone...that is the basic process described to me....

Is this ok to do for basic 101 cleaning of merc/lead? BUT, I have read that you have to dilute the nitric with water 7/1 OR the lead will attach to the gold if the nitric is a highly concentrated solution? True or not?....Also, do I need to heat the nitric acid prior to cleaning the gold? Lastly, seen some formula's that say mix the nitric/sulfuric and heat??????

Hope you can clarify a specific, basic, process for quickly cleaning up gold to sell....I'm reading so many different things, it gets confusing...wish there was a basic bible on these processes someone could refer to....

i have the plumbers sulfuric acid now....is it any help with cleaning up the gold?...

I have noticed that my fine gold flour dust and the small pickers are not that bright where I am digging....it was a dump on the nome beach years ago....so, i'm wondering if there is a chemical process going on here....

thanks for all the help, know your not here to specifically see what is up!

scotty

 

[Harold_V]

BUT, what i do need help with now is i was told by the dredgers here to clean my gold of my merc and lead, to just burn off the merc, quickly....then put nitric into the solution , it foams, it turns a different color...do it several times...it cleans up...put baking soda in fresh water, put into solution, rinse several times.....the lead is gone...that is the basic process described to me....
Is this ok to do for basic 101 cleaning of merc/lead?

While the preliminary process of heating gets rid of the mercury------I question the wisdom of doing it that way. You're releasing mercury to the atmosphere----which ends up somewhere -------somewhere that's not in anyone's best interest. A retort would be so much nicer! By the way, as far as I know, the baking soda is strictly to neutralize any residual nitric----although perhaps it has some washing qualities as well. In my opinion, it has little to do with removing lead. That should be handled by the dilute nitric.

BUT, I have read that you have to dilute the nitric with water 7/1 OR the lead will attach to the gold if the nitric is a highly concentrated solution? True or not?..

I have no experience with that process, but I interpreted what I read as the lead forming an impervious coating if boiled in concentrated nitric, not attaching itself to the gold. Nitric acid often performs far better when it is combined with some water----so don't attempt it without diluting----not much to be gained. I'm positive you misinterpreted what you read.

..Also, do I need to heat the nitric acid prior to cleaning the gold?

Personally, I don't understand how anyone words with cold nitric. I always heated when I refined-----and wouldn't think of working cold. If for no other reason, you never know when the work is done, or the acid is exhausted. What you accomplish in fifteen minutes with hot dilute nitric could well take 24 hours without heating, then you'd still wonder if the work was done, or if the acid was exhausted.

Lastly, seen some formula's that say mix the nitric/sulfuric and heat??????

Not for lead. Sulfuric will guarantee the lead does not dissolve-----I think. If it did, it would immediately be converted to lead sulfate. You're going to have to rely on Lou, Irons or GSP for the right answer for this one. I'm not a chemist, and used sulfuric strictly to eliminate lead that was in solution. Considering the source of the material I normally processed, it wasn't an issue--just a safeguard to insure that should any lead be present, it did not end up in the final product. You may know that lead destroys gold's ductility, and it takes very little to do so.

Hope you can clarify a specific, basic, process for quickly cleaning up gold to sell....I'm reading so many different things, it gets confusing...wish there was a basic bible on these processes someone could refer to....

It likely goes without saying that a guy that refines sees this entire issue differently. From my perspective, the gold should be refined. From your perspective, if I can speak for you for the moment, what you want to do is prepare your gold for market in the as-found but clean condition. If that be the case, I see no reason for sulfuric at all. If you boil your gold in dilute nitric, it will reach a point where it does nothing further. All of the free silver, copper and iron should have been dissolved, with the gold, being in the majority, protecting the balance from dissolution. The only thing I'd do after action ceased with nitric would be to boil in something that killed any traces of acid, so the gold was safe to handle when it was dry. You could also heat it to a few hundred degrees and allow any acid present to evaporate. A boil in tap water after the nitric process would certainly minimize any residual acids, so the heating process would likely work quite well for drying.

i have the plumbers sulfuric acid now....is it any help with cleaning up the gold?...

Not in my opinion, but I am not a chemist, as I already stated. Perhaps it will perform some useful function----can't really say with certainty. For damned sure, it won't remove lead.

I have noticed that my fine gold flour dust and the small pickers are not that bright where I am digging....it was a dump on the nome beach years ago....so, i'm wondering if there is a chemical process going on here....

Can't comment on any chemical process, but there's no particular reason for gold, as found in nature, to be bright and shiny, especially if it is alloyed with a high percentage of base metals. If I'm wrong, I stand to be corrected.

Harold

 

[Anonymous]

thanks harold for the help...

i've gotten some negative, "you don't know what your doing" crap from others, but, you gotta start somewhere....and asking questions is the best way to to....i always cross reference the answers, read up, etc til I feel safe to perform a process...so thanks for the guts to give a specific answer and referrals...

It seems that there is a kinda fear factor in answering some specifics about this stuff, so, thanks to all you guys that emailed me....and to the guys on the other sites that just were negative with no guts to give specific recommendations, hope that you are not around long on teh forums....with that type of tactics, someone could get feed up and try something without further research....

or quit gold mining...i'm in a bind, needing money and holding onto anywhere from 4 to 6 ounces of unprocessed gold with lots of lead and merc in it...and it was suggested on another gold forum that i 'walk away' from it since I did not know what was in my mining site.....not the attitude that is needed since there are processes for all of the problems we face...just takes time and research...

thanks guys for the help..

 

[Anonymous]

Maybe they know were your site is, and what is in it.

Jim

 

[Oz]

Good point James, you may have called that right. Refining some of what you find in the wild can indeed be deadly. It’s not at all like once refined material. Irons has told a story or two of events that have happened to him refining ore, and he is a chemist.

 

[Anonymous]

well...if i knew that you were a newbie to mining....and I knew specifically where you were, as suggested in teh prior two post.....adn that the site you were in was contaminated......I would say something...that would be my response...

"hey man, your at the XYZ site, I've bveen there, I know what is there...it is XYZ, you need the ABC process"....

but, hey, that's me...be specific....tell me what is there...not negative, round about statements of "oh, you should just break camp and leave" crap......because there is a process...

and there are other old miners that have been working the site ...so, it's workable....I just like to research others opinions before i take what is given to me as the only way to do things...forgive me...

so, if someone did know what was there, as suggested, it would be very irresponsible NOT to say something very specific....like, " i've been there, be careful because of...."

just the blind negative stuff gets to me....as I said, thanks for the guts here to suggest a specific process....I'm looking back up through the posts at all teh guys that have taken ALOT of time to nail out some specific processes...and hey, IT"S MY RESPONSIBILITY in the end...but at least I've seen some guys with some guts to name out some basic 101 processes for me to research, etc....

i've burned or mixed all my stuff outside, in the wind, staying up wind, etc....

so, I'll keep up the research...

funny though, I've seen this same negative tone in part of the hunting/trapping community since i got to alaska....down talking anyone new...or talking down anything hunted down south, etc.......or doing the, 'mines bigger than yours", thing...I actually have seen kids in the bush village afraid to hunt bear because of one or two guys that got big bears that down talk everyone else..so if it is not a freaking 9 ft bear, well, geez, you can't take it or you'll get laughed at...man, this p's me off....we finally got a kid, 13, to take a pretty 5 ft bear as his first since HE HAD to work it, not us...when he was done, crap, he said there was no way he could have taken a bigger bear!.... people need to think before they speak......I hope that there are not any kids on these forums...they'll get turned off real quick...

i hope i'm doing the right thing...asking questions, researching adn reading books given to me by the old miners here...if i listen to certain folks on these forums, I guess I should walk away form my ounces, from my mining site, and not research a specific process to conquer the problem....

i love being around self starters, positive people, gutsy opinions and conquerors....negative people just suck...and turn newbies and kids off to trapping, mining, etc...read back up through these posts and see the guys with specific opinions....thanks...

again, thanks for those that took the guts to suggest a process to conquer my problem so I can cash in on my hard labor....