Help with sweeps

[Rickthenewb]

Hi all, I currently have over 140 oz of mercury laden jewelry scrap. I bought a retort and am looking forward to using it. I have a couple questions. Is the retort supposed to get hot enough to melt the melt or just vaporize the mercury. Also the sweeps are made up of less then 1 percent mercury, 7% gold, 1%Pt, 34%silver, 28% Cu and over 30% of an unknown metal. I am wondering the best way to attack this. Any help will be appreciated. Thank you



rick

 

[aflacglobal]

http://www.goldrefiningforum.com/phpBB3/viewtopic.php?f=56&t=661

http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?t=1253&start=0&postdays=0&postorder=asc&highlight=

 

[Harold_V]

Sweeps that contain mercury are sure to be troublesome. When you attempt to retort, the included waxes and oils are going to be a problem, but I see no way around the process unless you digest the lot in sodium hydroxide (lye).

I advise you do your retorting in a room with positive evacuation of atmosphere, to insure you do not breath any vapors. I'm even more inclined to suggest you refuse to process the material, especially if you have no experience with retorts. Dying from breathing mercury vapors to recover some values isn't my idea of a good deal.

Avoid working with mercury unless you have no other options. How it came to be mixed with that kind of waste is a mystery to me----it has no place in refining precious metals. It is not advised for recovery of metals, either, although that hasn't stopped many from the pursuit.

In my estimation, the only material that a refiner should face that contains mercury would be dental waste. It should be handled with due respect, for the reasons mentioned, above.

Harold

 

[Rickthenewb]

Thank you Harold I appreciate the concern and understand the danger, the reason for this endeavor is I have a supplier who has a lot of antique jewelery sweeps (pre 1930's), it is my understanding that jewelry this old tends to have small amounts of mercury that came from the ore itself. I have a very good fume hood that I just had built with a very strong fan. Plus I have mercury cartridges for my face mask as an extra precaution. The percentage that I am charging is very good and there is much more of this stuff available. I though it would be worth it to have a small niche that most refiners do not want to attempt. I appreciate the help, I am just going to buy a book on the subject and I'll let you guys know my results. Any pointers are still welcome


rick

 

[nickvc]

The only mercury I can think of that was used in jewellery manufacturing was in the fire gilding process where the operators had a very short life expectancy.
Mercury and fine gold powder was mixed painted onto the items and then heated to vaporise the mercury leaving that rich gold colour seen on antique jewellery, this was used in the Victoian era and before but I'm fairly sure it would have died out by the 1930,s.
Are you sure there's mercury there? If your going to treat the sweeps your going to have to incinerate them and that's going to give off mercury vapours....not good!
The only other reason I can see for mercury been there is if someone misguidedly tried to use it to recover the gold.

 

[Backroads]

Rickthenewb

Sounds like your prepared for the mercury, I did'nt know they made mercury specific cartridges . . .I'm not sure if this has been mentioned, but standard repirators with activated charcoal filters, can have they're life extended, by keeping the respirator in a sealed tupperware container when not in use. I'm not familiar with the mercury cartridges though.
Having seen end stage, Alzhiemers disease I'm more afraid of what mercury does to the nervous system. "Mad as a Hatter" came from hatmakers, working with mercury, eons ago . . .I'm not so much afraid to die, as afraid to die horribly . . .just my two cents

Good Luck, Tim

 

[Harold_V]

Thank you Harold I appreciate the concern and understand the danger, the reason for this endeavor is I have a supplier who has a lot of antique jewelery sweeps (pre 1930's), it is my understanding that jewelry this old tends to have small amounts of mercury that came from the ore itself.

That's insane. Mercury vaporizes at a temperature well below the melting point of gold. If there's mercury present, it must have come from a different source.

I processed jeweler's wastes on a daily basis, and know how lucrative they can be. I hope I didn't sound like I was trying to discourage you, for that wasn't the case.

It might be wise to determine if the material really does contain mercury. I can't imagine how it might be there through normal channels. Anyone that has worked with gold understands how destructive it is to include mercury unless they used it for extraction from ores.

Harold

 

[dtectr]

The only other reason I can see for mercury been there is if someone misguidedly tried to use it to recover the gold.

that's my guess as well - someone at some point got a hold of some mercury & thought they'd just bypass that 'old crook refiner'
& probably recovered SOME values, but like stated earlier, is probably drooling somewhere with a cork on the end of his fork.

I shiver when i still read of someone using/reccomending the Irish potatoe retort used by the old-time prospectors :shock: :roll: :shock:

 

[goldsilverpro]

I agree with nick that it could be from fire gilding. A lot of those old techniques were still practiced by a few after they went out of vogue. Also, in this article, it seems like it might still be used, albeit rarely, for antique repairs when trying to duplicate the original technique used and the appearance. In fact, the author seems to be promoting it as a possible part of the jeweler's arsenal.

http://www.ganoksin.com/borisat/nenam/fire_gilding-9-3.htm

 

[Rickthenewb]

I bought these on ebay last week
http://cgi.ebay.com/MERCURY-RETORT-GOLD-RECOVERY-/260678473353?pt=LH_DefaultDomain_0&hash=item3cb1a5d689
More work is needed on the fume hood, i am adding FRP and a plastic fan next week, then I believe I am ready to go.
If you think I need more please let me know.

 

[Oz]

The mercury content could also come from gold jewelry that was accidentally exposed to mercury while it was worn. Once brought to a jeweler for repair, parts or all of the piece were put on the scrap pile.

 

[Backroads]

This is my fume hood

square, level, and plumb . . .

nothin half-a$$ed there!

(ahhhhh . .I need a thumbs up smiley . . .)

Nice Carpentry!!!

 

[nickvc]

I agree with nick that it could be from fire gilding. A lot of those old techniques were still practiced by a few after they went out of vogue. Also, in this article, it seems like it might still be used, albeit rarely, for antique repairs when trying to duplicate the original technique used and the appearance. In fact, the author seems to be promoting it as a possible part of the jeweler's arsenal.

http://www.ganoksin.com/borisat/nenam/fire_gilding-9-3.htm

GSP the only place that I ever heard of that still used this process was in Switzerland of all places, and very expensive, which really isnt too surprising given the risks..

 

[Palladium]

I have no knowledge in that field what so ever. I read that article with great interest and thought. I do have to say that somewhere in all that i get this OMG !!! feeling. They just talk to much about mercury this, vapor that and if im not mistaken i think that dude used the word brain damage. I'm telling you, I just can't afford to lose any more brain cells. I think of the people who don't use the proper safety precautions. As much as i practiced what i thought was proper safety practices that were thought of in the day to be the quality industry standards when i applied specialty coatings back when is was in my early 20's. I followed all the guidelines. Even with the proper training and the minimal exposure i had to the chemicals 20 years ago that would be where my cancer can be traced to. Point is i shiver when i think of procedures like that and the people who practice that trade.

Makes you wonder, How safe is really safe ??????

 

[Rickthenewb]

This may sound really amateur but couldn't I just wash the sweeps in some type of detergent to clean the grease and oil off?

 

[Barren Realms 007]

This may sound really amateur but couldn't I just wash the sweeps in some type of detergent to clean the grease and oil off?

Nope, you will still have traces along with traces of the detergent or soap you use.

 

[Rickthenewb]

So this is going to pose a problem, I have to retort the mercury out but I also have to burn off the grease. will Mercury retort at a temperature lower than the incineration of the grease?

 

[Barren Realms 007]

That is something I am not sure of because I have not looked into the process that much.

 

[Harold_V]

So this is going to pose a problem, I have to retort the mercury out but I also have to burn off the grease. will Mercury retort at a temperature lower than the incineration of the grease?

Let me be clear. When I read your first post, my head wrapped around the word sweep instead of scrap.

No, I don't know how I did that (it was not a part of your post), but it's not something I haven't done before. Some folks may consider me a bit of a moron. Sorry for the confusion.

Ok, lets get back to the subject at hand.

I expect you are talking about bits of gold, or even entire objects made of gold, commonly called jewelry. Lets go with that for the moment.

You can place them in a container of ammonia for a brief soak, which will remove oils and waxes (still to be found, but in far lower volume than my original thoughts). Most people don't clean their jewelry, so it's rather funky. My wife is likely the only exception I know. I'll provide a second choice, below.

When you heat to remove mercury (using a retort), my experience (processing dental amalgam only) was that there will always be a trace that does not get eliminated. You can minimize that problem by raising the temperature of the retort to the point where the condensing tube and all areas beneath it are beyond the evaporation point of mercury.

Now that I have my head out of that dark place, know that you can simply retort the material you have without cleaning. Expect it to stink a little---and maybe even to condense a little oil in the recovery---but it will work adequately. If you'd like to clean it so there is no odor, if you have access to some lye, that will do a perfect job. Rinse well after cleaning. You should now be residue free.

The condition I speak of was so horrible when running dental amalgam that I ran it under my large melting furnace hood, and had a strong detergent in the container where mercury accumulated. The smell was akin to that of burning your neighbor's dog.

Do use extreme care when retorting. Insure that the retort has a perfect seal.

Harold

 

[Barren Realms 007]

I did the same thing you did Harold...