# Jeweler’s Dirt



## Emmjae (Feb 19, 2011)

Hi folks,

I have been experimenting on some jeweler’s dirt I got from my local small town jewelry store. This is the dirt that was from his buffing wheel area. I received approximately 4.9oz. and it contains a lot of buffing compounds and fuzz from his wheel. 

I started out by sifting this dirt to remove the fuzz and larger chunks. I then ground the chunks and combined to the already sifted fine dirt. I took 1oz. of this dirt along with the fuzz and burned it down, ground it to a fine power and incinerated till it glowed orange in a dry melting dish. I then ran a magnet through the power and removed anything that stuck to it and set it aside for later.

I transferred the remaining powder to a 2L beaker and added 250ml of my cold recipe nitric acid diluted with a little distilled water. Set it on my hotplate/stirrer with a watchglass and set to a low heat and slow stir. I waited till the reaction stopped and added another 250ml of my diluted cold recipe nitric acid. After the reaction stopped I ended up with a lime green colored solution. I’m thinking good, I should have removed most of the garbage metals along with some silver.

I tested the solution with stannous in a white plastic spoon and on a filter paper. It showed very positive for gold. The color went instant jet-black. I have to assume something in the powder created an AR solution. Any idea what might have caused this???

My plan was to siphon off this solution and go straight to AR with the remaining powder in the same beaker. I have since done this and my AR was a beautiful golden yellow. Was able to control my nitric additions so no denox was needed. Have chilled with ice, filtered and dropped my gold with SMB with no problems.

Should I have started with HCL to remove my base metals? I figured nitric would do a much better job of removing the base metals but now I’m not so sure. I am now in the long process of denoxing my green solution by evaporation and addition of HCL. Any suggestions would be very much appreciated.

Thanks, Mike


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## Palladium (Feb 19, 2011)

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


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## Emmjae (Feb 19, 2011)

Thanks for the link. As soon as I saw it I remembered reading that a while ago and thought oh great, now I feel stupid again  . Sorry for the rehash of an old subject.

Mike


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## Palladium (Feb 19, 2011)

Nothing wrong with asking questions. 8)


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## Barren Realms 007 (Feb 19, 2011)

On your nitric solution that test positive for gold you can possibly add some SMB and drop your gold as I have done in the past. You might want to take a look at this thread and see if it helps you any.

http://www.goldrefiningforum.com/phpBB3/viewtopic.php?f=49&t=6026&p=87587#p87587


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## Emmjae (Feb 28, 2011)

Hi Folks,

Just had to let you guys know that my little jewelry dirt experiment has panned out. My local jeweler was very impressed with my return of 6.07 grams of twice refined gold from his 4.9 oz. trial bag of dirt. He has always felt that he has been way under paid by the guy that he has been dealing with. Now he knows. Too bad for the other guy because now I am going to be his refiner for all of his bench dirt in the future for a percentage of the gold. He claimed the guy that buys his dirt wouldn’t have even come close to the value of the gold I just handed him for all of his dirt. I’m going back this Friday to pick up my first batch, which looks like it will be well over 5 lbs. might be closer to 10.

He is also questioning what he’s been getting for his bench filings now too. He was talking about letting me refine his next batch of those too. :mrgreen: 

I couldn’t have done this without the help and information provided by this forum. I can’t thank all of you enough for what you’ve done for me and how it’s changed my life for the better. We could be talking new career / small business for this old man. Will let you know how this next batch goes.

Thanks again

Mike


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## stihl88 (Feb 28, 2011)

That's great news Mike, it just goes to show how honesty is the key ingredient.


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## joem (Feb 28, 2011)

These are more of the personal stories of success we should write about. Being a mentor to newbies will go a lot farther than than just a director.
Excellent job Mike, keep us updated,


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## Harold_V (Mar 3, 2011)

Mike,
What you just experienced was precisely how I got started refining for others, and resulted in my prolonged refining career. 

The first lesson I learned was that honesty was of uppermost importance. Treat the customer fairly and you have them for life. 

My hat is off to you. 

Harold


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## PreciousMexpert (Mar 4, 2011)

Emmjae
Harold was saying incinerate 
sieve 
boil in HCL 
than AR 
than usual stuff for polishing dirt with gold.
with this process if there is silver in the solution it falls to the bottom as scums than you use nitric to get the silver
Would this be a corrected summary of this process


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## Harold_V (Mar 4, 2011)

PreciousMexpert said:


> Emmjae
> Harold was saying incinerate
> sieve
> boil in HCL
> ...


When processing this type of material, it's best that you make a decision up front on the recovery of silver, or simply allowing it to remain in the waste, for future recovery. The reason is that the silver is generally very finely divided. The HCl treatment is done hot, so silver is converted to silver chloride, which is not recovered by nitric at a later stage of processing. 

So then, armed with this idea, a decision should be made up front on what your recovery purpose should be. If you do a nitric digest instead of an HCl wash (after screening), the resulting solution most likely will not filter well, if at all. When I'd process wastes from a silversmith's bench, one that did only a small amount of work in gold, I'd do the nitric process instead. Once I had recovered the silver (I allowed the solution to settle, then I'd siphon instead of try to filter), I would then incinerate the material, then revert back to the HCl hot wash. Without that, filtering the resulting gold bearing solution that would follow would be extremely difficult. 

I hope this makes sense. If I leave you confused, please ask for clarification. 

Harold


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## PreciousMexpert (Mar 5, 2011)

Hi Harold 
That help a lot because I was a bit confused
Thanks


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## PreciousMexpert (Mar 5, 2011)

I was also wondering about the acid after all the valuable metals were cemented.

What do do with this acid ,can it be used for something or is it neutralized and thrown away and what is it called
Thanks


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## Harold_V (Mar 5, 2011)

PreciousMexpert said:


> I was also wondering about the acid after all the valuable metals were cemented.
> 
> What do do with this acid ,can it be used for something or is it neutralized and thrown away and what is it called
> Thanks


I can't speak on the subject of reclaiming. In my case, when values had been extracted, heavy metals were removed from solution and the solution discarded. 

Lazersteve had done considerable research on the subject of recycling solutions. Perhaps he can provide guidance.

Harold


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## golddie (Mar 5, 2011)

I am thinking maybe the waste acids can be used for making colorful beads.
For example copper nitrate would be good for that and maybe even iron nitrate, I am not exactly sure if the term iron nitrate is correct


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## Refiner232121 (Mar 5, 2011)

I know that if there is tin in the solution you add sulfuric acid and it falls to the bottom 
I think lead also falls to the bottom but I am not sure about that
Thanks


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## lazersteve (Mar 5, 2011)

golddie said:


> I am thinking maybe the waste acids can be used for making colorful beads.
> For example copper nitrate would be good for that and maybe even iron nitrate, I am not exactly sure if the term iron nitrate is correct



Copper nitrate readily absorbs water from the air and would not be good for jewelry beads. Copper Sulfate will form nice crystals that keep their shape in the air.

Copper nitrate can be recycled by several methods posted on the forum. Use the search tool and put in Cu(NO3)2 by author lazersteve or search on copper nitrate. It has many uses from making nitric acid to dissolving sterling silver electrolytically.

Steve


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## Emmjae (Mar 6, 2011)

Thanks guys for the vote of confidence and for the replies to PreciousMexpert's questions.

For some reason Internet Explorer would not let me log in to the forum since Friday morning. The home page would come up but it would error whenever I tried to enter the site. I tried on 3 different computers. Thought maybe I got banned for some reason...lol.

I would like to add that I was able to recover about .95 grams of silver from my trial batch just from collecting the silver chloride that formed by using ice to dilute my warm solutions after siphoning between AR batches and evaporations. Possibly because I might not have boiled long enough with my HCL before going to AR.

Mike


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## Frankk12 (Mar 6, 2011)

> I know that if there is tin in the solution you add sulfuric acid and it falls to the bottom
> I think lead also falls to the bottom but I am not sure about that
> Thanks


Lead does fall to the bottom as well in AR


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## golddie (Mar 6, 2011)

Hi Mike
You add the ice to dilute and the AR and the silver stays in the solution and gold falls.
Do you use copper to cement the silver that remains in that solution
Thanks



> I would like to add that I was able to recover about .95 grams of silver from my trial batch just from collecting the silver chloride that formed by using ice to dilute my warm solutions after siphoning between AR batches and evaporations. Possibly because I might not have boiled long enough with my HCL before going to AR.


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## Emmjae (Mar 6, 2011)

Hi Golddie,

I use ice to dilute my solutions instead of pouring in water. It seems to form the silver chloride better and faster. (Something I learned reading various posts on this forum) I let it settle, siphon and then filter the solution so it’s crystal clear before I drop my gold. 

The remaining silver chloride is washed and treated with either sulfuric acid / iron bar or with sodium hydroxide/corn syrup. Both methods are on video on Lazersteve’s website and explain the process very well.

I use copper only after my gold is dropped to recover any possible gold missed and for the PGM's that may be left behind.


Mike


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## golddie (Mar 6, 2011)

Hi qst42know

Thanks for helping out.
I have a lot to learn from a pro like you
Take care


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## golddie (Mar 6, 2011)

Hi Mike
I appreciate your help
These are steps I have not gone threw and they are confusing me
Take care


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## qst42know (Mar 6, 2011)

golddie said:


> Hi qst42know
> 
> Thanks for helping out.
> I have a lot to learn from a pro like you
> Take care



Not a pro, not by a long shot.


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## qst42know (Mar 6, 2011)

Great job on your new project Mike. I do love hearing of examples where honesty trumps greed.


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## golddie (Mar 11, 2011)

I was talking to jeweler yesterday and it seems like there is very little room for little league refiners like those of us here in this forum to make money from this.
From what i understood by talking to a jeweler he takes his polishing dirt to a person that does refining and they incenerate in front of his eyes and he says he gets back a chunk of unrefined gold
Than he can take that to a company here that has an xray machine and check the karat and give 1 or 3 percent less than spot gold.
Forget about processing scrap gold if these figures are right
I wonder what Harold would do in times like this.
It isn't like those old days
Also I am assuming that after they incenarate they mix the dirt with flux and pour it to a cone mold


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## goldenchild (Mar 11, 2011)

golddie said:


> I was talking to jeweler yesterday and it seems like there is very little room for little league refiners like those of us here in this forum to make money from this.



Of course this there is room for "little league" refiners to make money refining. This thread is testament to it.


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## golddie (Mar 11, 2011)

Maybe if you are in a small town and there isnt a person that incenrates the polishing dirt in front of you and gives back a lump of gold


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## golddie (Mar 11, 2011)

Hi Emmjae
Do you live in a small town
I live in Montreal and the new place that opened up is in the same building as Kitco 
These guys are on the 10th floor and I heard they have an xray machine and they pay you on the spot


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## 4metals (Mar 11, 2011)

If they are burning it in front of him and fluxing and melting in front of him, you should ask him if he takes his slag and residue from the processing back. If he does, offer to refine it for him. If he doesn't tell him he should take it next time. 

From the process you described, the guy doing the burning is keeping most of the value as it will not come down into a bead without a collector. I'll bet the guy doing the burning doesn't throw the residues out. 

Of course the only customers the incinerating and melting guy can get are the "little league jewelers" ! :lol:


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## nickvc (Mar 11, 2011)

As usual words of wisdom from 4metals. I must admit I'd like to have the residues to treat they must be loaded with precious metals :shock:


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## Emmjae (Mar 11, 2011)

golddie said:


> Hi Emmjae
> Do you live in a small town
> I live in Montreal and the new place that opened up is in the same building as Kitco
> These guys are on the 10th floor and I heard they have an xray machine and they pay you on the spot




Yes I would say it's considered a small town. Only 1 Jewelry store, family owned and the owner is 5th generation. What might help me along for this area is there isn't any kind of refiner close by as far as I can find. He claims the guy who buys his bench filings fly's in once a month to purchase his stuff. Not sure where he's from...yet 8) .

I figure once this customer is satisfied I'll look into finding a second and so on....

Mike


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## golddie (Mar 11, 2011)

Hi 4metals
That is a very good answer and I will have to try to convince these jewelers I know about what you said.
The thing is if you try too hard than they get suspicious.

The people doing the burning is not in that same building 
They 2 different people

Hi Emmjae
That sounds like a good place to live, I like small towns
I would like to be like you and treat them in a way I would like to be treated if I was in their place. 

Thanks


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## 4metals (Mar 11, 2011)

> The thing is if you try too hard than they get suspicious.



What you are selling is that you understand what is happening to his material and that you would not pursue the recovery in the way he does. 

In 1995 Roland Loewen wrote an excellent book called "Small scale refining of Jewelers waste" an excellent book that all on this forum interested in processing material generated by jewelers should read. In his book he discusses melting sweeps in a crucible in a gas melter. 

He details a specific flux mixture and a fixture made specifically to determine the relative fluidity of the flux. bottom line is he did not use a collector. This book set the medium sized refiners in the industry to buzzing and I know of more than one house who tried this method. 

He mentions the burnt sweep should be mixed with the flux and slowly added to the crucible until the entire mass is molten. This alone, adding until it is all in and molten, often takes well over an hour. Then he suggests keeping it molten for a minimum of 1 hour to allow all of the particles to come together to form a bar. So with a small jewelers lot, maybe 20 pounds, incineration can take an hour or more, then fluxing and melting another 2 hours minimum. By the time you get your button and leave I'm guessing it is a good 4 hours. (for 20 pounds) How long is your jeweler waiting for this process? An important fact to know. 

I admit I tried this method as well. For some sweeps it worked for others it didn't. Having assayed all sweeps before processing it was easy to see this method worked better for the sweeps assaying 7 or 8% precious metals per pound. These were the best of the best sweeps, and usually the exception rather than the rule. The lower the metal content, the worse the process worked. At that time I had access to a Cutler Rotary Furnace and I also conducted sweeps melts using Loewen's flux formula plus copper as a collector. The difference was night and day, the copper collector, benefiting from the rotating of the furnace and the reducing flame, effectively removed 98% of the metal. 

If they are adding copper, they must some-how roll their crucible to allow the swirling pool of molten copper to collect the small particles of gold in the sweep. It is easy to tell if copper was added, the bar will be pink and much bigger than expected. What color is your jewelers bar? 

I could of made a good living off of the gold left behind by straight melting the sweeps in a fixed crucible without copper as a collector. 

So 3 questions for your jeweler.

How long did the incineration and melt take?
Did the operator rock or remove and swirl the crucible routinely?
Was the bar pink?

If the time was less than 4 hours, the crucible wasn't swirled routinely and the bar wasn't pink, ask him to retain all of the slag from the process and offer to have it assayed for him. There is only one way for the guy burning and melting the sweeps to make money, (Other than charging $1000 for the service) and it is in the residues.


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## golddie (Mar 12, 2011)

Hi 4metals
Thanks for that detailed explanation 
I will have to re read it again later
I did a quick search of a collector and there is not much
Is there already a thread on this subject and maybe a bit more info


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## 4metals (Mar 12, 2011)

A collector is a metal that is put into the melt to increase the overall percentage of metal in the melt. The more metal in a melt, the larger the pool of molten metal and the larger the percentage of the individual particles being caught, or collected, by the molten metal pool. 

When sweeps are in a flux and the entire melt is fluid it is still difficult for very very small metallic particles to settle through the flux and collect as a large metallic mass. The collector makes the pool larger. The rotating of a melt increases the chances of the tiny particles of encountering the pool of metal which remains at the lowest point in the furnace while the flux (and small particles of gold trapped in that flux) move above it.


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## Frankk12 (Mar 12, 2011)

Would the collector be lead


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## 4metals (Mar 12, 2011)

In a fire assay sweeps fusion the collector is lead, the lead goes in as litharge (PbO) and as a result is spread throughout the fusion. As it melts it collects the fine particles of gold. The lead is in a ratio much higher than the gold in the fusion, so using lead oxide as a collector in a furnace recovery would require a lot of lead. Plus lead is not a metal you want to be around if you don't have to.

I would suggest copper for a collector or silver if you have it. The benefits of the silver is the bar you produce will be pre-inquarted and only require parting. The silver is easily recycled by cementation.

Copper is used because for a large melt you are putting in copper at the rate of 1/2 pound copper for every pound of sweeps. These copper bars are either refined electrolytically, or sold to a large copper refinery that pays on all PM's and copper.


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## golddie (Mar 12, 2011)

Hi 4metals

Thanks very much


> Did the operator rock or remove and swirl the crucible routinely?





> If they are adding copper, they must some-how roll their crucible to allow the swirling pool of molten copper to collect
> the small particles of gold in the sweep.




You swirl the crucible
I think I get it


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## Emmjae (Mar 16, 2011)

Hi folks,

Just wanted to follow up on my first job with my local jeweler. He started me off with just under 3 lbs. (47.4 oz.) of buffing wheel dirt along with some filters. He was estimating an ounce of gold possibly and I was able to refine 52.56 grams. I think he’ll be happy. :mrgreen: 

I attached a photo fresh out of the water bucket. This was my first attempt at making shot too…lol.

Mike


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## Barren Realms 007 (Mar 16, 2011)

That is some beautiful looking stuff there. Congrats to you.


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## Harold_V (Mar 16, 2011)

Wow! You catch on fast!

Excellent job.

Harold


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## Oz (Mar 16, 2011)

Fantastic work! Sweeps can be a pain to refine to fine gold and your results speak for themselves. That is some nice looking shot to boot, maybe you would like to talk about the process you used for shotting your gold.

Job well done!


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## Refiner232121 (Mar 16, 2011)

Hi Emmjae
That looks really good 
Congratulations
It would be nice to give details if you can 
step by step
Sorry for asking for too much
I have also done polishing dirt and it is really labour intensive
For example how many times did you boil and siphon in the AR.
and I guess you do this until the AR does not show gold with the Solution A
Thanks


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## 4metals (Mar 16, 2011)

> He was estimating an ounce of gold possibly and I was able to refine 52.56 grams



That's 70% more than he expected. He was obviously dealing with a less than creditable refiner. Seems like you've got his attention and maybe even a long term customer. 

Good work.


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## Emmjae (Mar 16, 2011)

Hi folks,

Thanks for all the great compliments. It means a lot to me coming from my favorite online teachers.

Oz: As far as how I made my gold shot, I took the advice from one of Harold’s posts and watched Steve’s excellent video and came up with a plan based on what I had on hand. 

Don’t laugh too hard but I didn’t have a stainless steel container that I could put 12” of water in so I used a 5 gal. Bucket and an old stainless steel dog bowl to set in the bottom. It was almost a perfect fit. Also made it easy to retrieve my gold without having to dump all the water. Just lift the bowl up. 

I then drilled an 1/8” hole in one of my 100 DWT silica melting dishes and form fitted it into a piece of firebrick making sure I had a large enough hole in the brick to allow for easy flow through. I placed the firebrick on the edge of a table with some steel to protect the edge and rigged a map gas torch so the hottest part tip was on the hole I drilled. Centered the bucket under the prefluxed melting dish and blocked it up. The distance from the dish to the water ended up being approx. 22”. Fired up the torch to heat up the dish while I started melting my gold with another set up. 

When my gold was ready to pour I gave the water in the bucket a vigorous stirring and slowly pour my gold into the dish. I firmly believe the key is the water agitation. The shot got flatter near the end of my pour when the water swirl had slowed down. Needed a third hand to keep it going..lol. I will come up with a way of doing that mechanically for next time.


Refiner232121: As for a step by step guide on how to process polishing dirt, this was my second attempt at this process and I’m no where near an expert. However here is a brief list of the steps I have done.

1: Incinerate everything and sieve through a fine mesh strainer. Remove any large metal bits, glass and trash. Grind and sieve again. Anything left I put into a separate container. Incinerate again.

2: Run a magnet through the incinerated power and put anything that sticks into the separate container from above. I process this the same way but keep it separate from all the other batches.

3: Do several low boils in HCL or until there’s no significant change in color. Check with stannous and save to reclaim some of the silver chloride that may have accumulated.

4: Do several low boils in AR, (I boil for 6 – 8 hrs per run), combine and evaporate, filter and drop gold.

I feel that you have to make the decision on how many times you boil your dirt in AR. The quality of the material will never be the same. I watch the intensity of my stannous test per batch and take it to a point of what I believe is a fair stopping point based on time and material expense needed to process. It’s reaches a point to where it will cost more that the gold is worth to retrieve it.

I also believe there is a ratio of material amounts to chemical amounts needed based on the size of vessel you are using to get the best results with the least amount of time and AR boils. That ratio is still a mystery to me and I will keep working at it till I find it.

Hope this helps and thanks again.

Mike


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## nickvc (Mar 17, 2011)

Emmjae when I was refining sweeps I used to find that if you had heated the AR and stirred the powders regulary your sweeps would yield around 90% of the total there in the first digestion so if I found 100 grams in the first digestion there would be 10grams left to extract in the next digestion and 1 gram in the next. This was never spot on but never far off but one difference that might cause a variance is that I used. 12 inch filter beds with good vacuum extraction, hope this helps and confirms what you found.


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## Refiner232121 (Mar 17, 2011)

Hi Emmjae



> 4: Do several low boils in AR, (I boil for 6 – 8 hrs per run), combine and evaporate, filter and drop gold.



You boil with the hot plate on low 
6 -8 hrs is something I was not doing 
Is it necessary to boil for so long

I have noticed in your fume hood that you have those vibrating machines
I don't think Harold had one of those but it seems like a good idea.
How much do they cost,is guess the vessel is heated when it is being vibrated and how much do they cost

Thanks for all the details I will read them more carefully later on
Take care


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## golddie (Mar 18, 2011)

> I then drilled an 1/8” hole in one of my 100 DWT silica melting dishes and form fitted it into a piece of firebrick
> making sure I had a large enough hole in the brick to allow for easy flow through. I placed the firebrick on the edge
> of a table with some steel to protect the edge and rigged a map gas torch so the hottest part tip was on the hole I
> drilled. Centered the bucket under the prefluxed melting dish and blocked it up. The distance from the dish to the
> ...


Hi Mike 
I am reading your post carefully and I dont understand this part very much,would it be possible to explain this a bit more or maybe a photo
Thanks


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## golddie (Mar 18, 2011)

I think I will have to buy a magnetic stirer
I boiled some 10K gold and I saw that it needed stiring all the time and this is needed for plishing dirt.
Where is the best place to get one of these things at a good price.

I also tried to make one of these stirrers and the magent broke the motor 
I know that there is thread about that in this forum but I was not able to benefit from it

I was wondering if Harold used one of these things.
Thanks


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## golddie (Mar 18, 2011)

Emmjae 
How about vacuum filtering 
http://www.amazon.com/Vacuum-Filter-Kit-Hand-Pump/dp/B003SSM77K/ref=sr_1_47?ie=UTF8&qid=1300459394&sr=8-47
I am thinking of buying one of these
Did you have one of these things

I think 4metals had a link to a simple vacumm pump device 
I am trying to find that but I cant 
I would like to order just a simple pump 

I think I found that link
http://www.crscientific.com/aspirator-pumps.html
http://www.crscientific.com/vacuumpumps.html
Which would be a better buy
There is even a metal kind 
Since this will be used for water only I think that might be a better choice
Thanks


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## golddie (Mar 18, 2011)

http://www.lmine.com/mm5/merchant.mvc?Screen=PROD&Store_Code=LMS&Product_Code=18533&Category_Code=hotplates_stirrers

This looks good 
Hotplate Stirrer


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## glondor (Mar 18, 2011)

Here is a nice alternate sight that seems to have good prices. Posted before by GSP I think.
https://www.pelletlab.com/


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## golddie (Mar 18, 2011)

glondor
Thanks for that link and thanks to Chris as well.
The price is also much lower



> Magnetic Stirring Bars


Is it a good idea to use one of these


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## qst42know (Mar 18, 2011)

golddie said:


> Emmjae
> How about vacuum filtering
> http://www.amazon.com/Vacuum-Filter-Kit-Hand-Pump/dp/B003SSM77K/ref=sr_1_47?ie=UTF8&qid=1300459394&sr=8-47
> I am thinking of buying one of these
> ...



Here is one that takes less water pressure to opperate and a lower price.

http://www.amazon.com/Aspirator-minimum-water-pressure-vacuum/dp/B003NUWGM4/ref=pd_sbs_indust_2


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## golddie (Mar 18, 2011)

Hi qst42know
Thanks for that link


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## Emmjae (Mar 19, 2011)

Refiner232121 said:


> Hi Emmjae
> 
> You boil with the hot plate on low
> 6 -8 hrs is something I was not doing
> ...



Unless I’m doing something major wrong (which is usually the case) 6 to 8 hrs is what it seems to take for my reactions to complete. At the moment I use a 2-liter beaker without a pour lip and a small saucer for a watch glass. With no pour lip on the beaker I get a pretty good seal so I have very little loss in fumes.

I keep my solution temperature just below the boiling point. When I see that I am not producing anymore of the tiny fizzing type of bubbles, I’ll stir my solution and observe. When I see no more fizzing bubbles I feel that my nitric acid has been consumed. I’ll then let it cool, siphon off and add a fresh batch of AR.

I start off using a 3:1 ratio for my first AR boil. After that I go to a 4:1 ratio. My nitric acid is homemade using the cold recipe formula found here on the forum. I’m not too concerned with having added too much nitric acid in my final AR boil because I evaporate my solutions to cut down on volume.

I have used my magnetic stir/hot plate to run my polishing sweeps but I found it harder to see if my reaction has completed. It also took the same amount of time so I saw no real benefit. Also if you stop the stirring at any point during the reaction, the materials settle on the stir bar and it’s very difficult to get it going again.

I mainly use my magnetic stir/hot plate for making my cold recipe nitric acid. It works excellent for getting all of the sodium nitrate dissolved in the water and having a constant stirring action while adding the sulfuric acid. I can produce enough to make 1-liter of nitric acid at a time for a cost of less than $10.00 per liter.

The magnetic stir/hot plates can be very expensive if buying new. I purchased both of mine from eBay. It took a couple of months but got them both for under $110.00 each shipped. I purchased my stir bars from eBay too. Found a 20 piece assortment ranging from ½” to 3” in lengths for $48.00 shipped.

Mike


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## stihl88 (Mar 19, 2011)

You sweeps are more than likely karat scrap and would therefore have some silver content which would slow down the AR process. If this is the case then perhaps next time you could perform a small experiment and take a sample of perhaps 10g of normal sweeps and 10g of sweeps after having been inquarted and processed in nitric, how much inquarting per karat of scrap that is required would be a hard one to guess given the different grades of karat scrap the jeweler has processed but you probably couldn't go wrong in regarding it all as 12k but this would depend on how much silver was already in the sweeps...


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## Emmjae (Mar 19, 2011)

golddie said:


> > I then drilled an 1/8” hole in one of my 100 DWT silica melting dishes and form fitted it into a piece of firebrick
> > making sure I had a large enough hole in the brick to allow for easy flow through. I placed the firebrick on the edge
> > of a table with some steel to protect the edge and rigged a map gas torch so the hottest part tip was on the hole I
> > drilled. Centered the bucket under the prefluxed melting dish and blocked it up. The distance from the dish to the
> ...



Hi Golddie,

Check out Lazersteve’s web site and look under his melting video’s. That will give you a very good idea of what I was doing. I used firebrick to hold my melting dish because I didn’t have the ceramic blanket. I elevated my dish above my water source so I could agitate the water before I poured.

At the moment I am still using the hand operated vacuum pump like in your link. I would love to set up a water supplied vacuum source but I’m on a city water hook up and my water bill is too high as it is. I don’t have the room to set up a water holding tank with a pump to operate a water type system. I will probably end up making my own set up using an old air compressor unless I find a vacuum pump at a decent price.

Hope this helps,

Mike


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## Emmjae (Mar 19, 2011)

stihl88 said:


> You sweeps are more than likely karat scrap and would therefore have some silver content which would slow down the AR process. If this is the case then perhaps next time you could perform a small experiment and take a sample of perhaps 10g of normal sweeps and 10g of sweeps after having been inquarted and processed in nitric, how much inquarting per karat of scrap that is required would be a hard one to guess given the different grades of karat scrap the jeweler has processed but you probably couldn't go wrong in regarding it all as 12k but this would depend on how much silver was already in the sweeps...




Hi stihl88,

You have me a little confused. I think were talking about different kinds of sweeps. I was refining polishing sweeps (more like a powder or dirt) and I believe your talking about what I would call bench filings/sweeps (more like small metal bits). I'm not sure how to inquart a powder/dirt.

Mike


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## nickvc (Mar 19, 2011)

Emmjae my only comment on your processing technique for sweeps is please make sure that you stir the sweeps powder in your beaker as it heats or else you will get breaks and possible losses otherwise seems good to me 8)


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## stihl88 (Mar 19, 2011)

Emmjae said:


> stihl88 said:
> 
> 
> > You sweeps are more than likely karat scrap and would therefore have some silver content which would slow down the AR process. If this is the case then perhaps next time you could perform a small experiment and take a sample of perhaps 10g of normal sweeps and 10g of sweeps after having been inquarted and processed in nitric, how much inquarting per karat of scrap that is required would be a hard one to guess given the different grades of karat scrap the jeweler has processed but you probably couldn't go wrong in regarding it all as 12k but this would depend on how much silver was already in the sweeps...
> ...



If it's in powder form then it shouldn't take that long to dissolve in AR. Ive never processed powder before but if it has more than 10% AG content then i would think that this could be what's slowing the AR process even though it's in powder form. Other than that perhaps invest in some 70% Nitric and see how it goes compared to the Cold Nitric recipe. 

I don't think your doing anything wrong if your dissolving all the powder but if your going to be doing a lot of this stuff then it would help to speed up the process a bit.


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## 4metals (Mar 19, 2011)

Sweeps never dissolve totally in acid they usually only have 10% (at most for jewelry sweeps) of their total weight as metal, there is always a lot of insoluble material.

The volume of the undissolved is why I suspect it was put up in acid a second time.


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## golddie (Mar 22, 2011)

Here In Montreal things are different than where Emmjae lives.
The stories of refiners ripping off jewelers is common everywhere.
That's why the honest guys is also affected by those things.
I called a jeweler and told him that I am refining polishing dirt and he said he is also going to that person that melts in front of the customer and he said the process takes 3 hours but they don't add any collectors.
He said he leaves the flux there because if looks clear and no gold there
I told him the story 4metals told us and he just listened and said I will try you next time.

I also called anothe jeweler and he takes is dirt to Johnson Matthew
He said if he can wait while I refine for him. 

He can trust JM but not me.

The mistrust here is unbelievable, and I don't blame them because too many jewelers were ripped off
I am thinking of trying to get there business.
They all want to be there when the refining takes place so I said why not give them what they want.
The only problem is that once they lean how to do this, they can always go up to their country home and refine over there
and they will not come back

Does anyone have a better idea.


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## nickvc (Mar 23, 2011)

Golddie refining sweeps isn't the easiest or quickest process if your talking polishing buff papers or floor sweeps and doing it in one day is almost impossible. To get a decent result it needs to be incinerated, slowly to avoid losses, milled and screened before you start any refining process. The actual recovery of the metals in acids is also a slow process and needs constant attention at the start as the solution heats up to avoid hot spots in your beakers and regular stirring helps to get the acid into all the powder. The filtering alone can take hours even with decent vacuum pumps and large filter beds so I'd be tempted not to promise a day turnaround. 
If I was in your situation I'd try offering to refine their lemel/ bench sweeps/ filings whatever description they use, this is much easier to complete in a day. If you incinerate it first then you can go straight to AR and recover the gold very quickly but will leave the silver as a chloride and any PGMs in the solution which can be cemented out later. Most jewellers are only interested in the gold unless they work with a lot of platinum or silver and a fast accurate result on their lemel may be your way to impress, but be aware that the recovered gold may not be 999 so another refining may be required if they want to re use it. The silver and any PGMs may be your profit and the silver chloride will have a small gold content also so it's a balancing act to get the deal good for both parties but it might get your foot in the door.


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## golddie (Mar 23, 2011)

Hi nickvc
Thanks for your reply.
From talking to people I am realizing that refining is not as easy as reading the threads in this forum.
For example the jeweler tells me that how can I trust you.
But he can trust JM.
He is giving his dirt blindly to a refiner he does not know and there is no guarantee that JM is not going to cheat him.


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## nickvc (Mar 23, 2011)

They might not cheat him but he will get hit with minimum charges which can be considerable. When I worked for JM here in the UK we charged pennies to treat sweeps but the returns were laughable or sad if they were your sweeps and I remember we had a rack in the safe full of sweeps bars with no owners....nice bonus!


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## 4metals (Mar 23, 2011)

Nick is right JM is a big house and they will have minimum charges and minimum deductions and all they will do is burn crush and sift and give you a sample on the same day. You will still need to have that sample assayed. 



> He said he leaves the flux there because if looks clear and no gold there



If he says the flux is clear he is probably just yessing you to death, the sweeps in the slags are as opaque as they can be. Generally you would never see flakes of gold as the gold in the rouge is microscopically small to begin with.


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## golddie (Mar 23, 2011)

I asked that jeweler who went to the refiner that melted their polishing dirt ,how much did he charge and he said $2,000.
3 hours of melting and plus he keep the flux.
The refiner told him that you can take the flux but as you can see there is nothing there 
So the jeweler said 
keep it.


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## 4metals (Mar 23, 2011)

I assume it was a relatively small lot. How much gold did he get back? Then you can figure what percentage he was paid to recover impure gold which had to be sold for a discount. 

He got hosed, there is room for you to work there.


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## golddie (Mar 23, 2011)

Hi 4metals
I should have asked him but I didn't 
Anyway I can ask him next time I see him.
I might consider making my place like a self serve refinery.
Polishing dirt will take at least 2 days so they will have to take that into consideration
Charge them a certain fee and they can do whatever they want and I can provide assistance.
Some of them will not come back again
Because once they learn they will not need me or my place
But some will come back


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## nickvc (Mar 23, 2011)

Probably not that black and white....these guys are jewellers not refiners so don't think they will want to change track...given them a few dangerous AR fumes and a small sniff thereof and most will leave it to you, just be sensible on your charges and treat them well and you will get plenty of work!


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## 4metals (Mar 23, 2011)

Let me get this straight, you're willing to let someone you barely know come into your refining space and handle acids and perform all the tasks required for a fee?

How do you spell LIABILITY?


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## Oz (Mar 23, 2011)

I would not want the liability of anyone in my lab.


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## golddie (Mar 23, 2011)

Hi 4metals
I guess it will be me who will have to do the refining


> How do you spell LIABILITY?


So I don't think there is something wrong with that.


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## Frankk12 (Mar 23, 2011)

There is also the danger of being robbed
They could come and survey the shop and than robbery could happen
I say be careful 
or take a picture of everyone that comes into our shop with a cell phone and record it somewhere and let them know about that.


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## Emmjae (Mar 23, 2011)

golddie said:


> Hi nickvc
> Thanks for your reply.
> From talking to people I am realizing that refining is not as easy as reading the threads in this forum.
> For example the jeweler tells me that how can I trust you.
> ...



Hi Golddie,

I can’t tell you how to get this guy’s business but here is a suggestion based on how I got my foot in the door with my first customer. What I did was offer to do a sample for him at no charge or percentage of the gold. This shows that you do know what you’re doing and also gives him some confidence in your honesty. 

I would ask him for a good mixed sample of say 5% or 10% of his next load of material. This will allow your customer to compare the yields between you and the other refiner. More than likely you will show him a far greater percentage of the yield. If so I don’t think you’ll have much of a problem getting his business in the future. Good luck.

Mike


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## goldnugget77 (Mar 30, 2011)

Hi Emmjae
I did hcl a few times
than I did AR for about 1 hour and siphon
than I did AR for about 6 hour and siphon
Now I am planning on siphoning the AR and than pouring all that dirt into a filter and washing it with water 
Than I my Ar will be kind of diluted so I guess I will have to boil it so I have less water and than I will precipitate 
Does this sound correct to you or could I do things differently
Thanks


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## Harold_V (Apr 1, 2011)

goldnugget77 said:


> Than I my Ar will be kind of diluted so I guess I will have to boil it



Lose the *"boil it"* idea. One does NOT boil solutions in order to evaporate. 

Harold


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## Emmjae (Apr 1, 2011)

goldnugget77 said:


> Hi Emmjae
> I did hcl a few times
> than I did AR for about 1 hour and siphon
> than I did AR for about 6 hour and siphon
> ...



Hi goldnugget77

As Harold said...DO NOT BOIL to evaporate. It's sounding like you’re on the correct path but I don't have enough details to give you an accurate answer. As I said in previous posts this was my second attempt at polishing wastes. I am by no means an expert. 

If you haven’t do so yet, please do a forum search on polishing sweeps and you will find excellent information under Harold V’s posts. I followed his instructions to the best of my capabilities and had very good results.

Mike


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## Frankk12 (Apr 8, 2011)

AR for 6 hours than than filter it
Than boil again in AR one more time add sulfuric acid than filter again
remove nitric by evaporation than dilute with ice
Filter again
than cementation
In all I am doing 3 times of filtering and i would like to know if this is too much
How many times of filtering is done is this process

Emmjae can you tell me what kind of filter you used
I am going to order the whatman filters but for now I use 5 coffee filters


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## Emmjae (Apr 8, 2011)

Hi Frankk12,

I boil in AR, let it settle and then siphon off. No filtering. This is done however many times you think is needed. I then rinse the remaining sediments through 4-5 coffee filters. Combine all liquids. Then add a little sulfuric acid and evaporate to reduce the volume and drive off any excess nitric. 

When you’re sure you have removed all the nitric, I add in about half of the original volume in ice. I let the ice melt and any sediment settle. I then siphon off and filter through a large funnel with a charmin plug on my vacuum filter flask setup. The charmin plug has consistently given me a crystal clear solution every time and is a lot cheaper than the better grades of filter paper. Just takes a little practice on how much charmin tissue to use as the plug. 

Mike


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## PreciousMexpert (Apr 9, 2011)

Hi Emmjae
How do you incenerate the polishing dirt.
Do you do it like Harold with gas and pass over it with oxygen or do you use a hot plate with strong heat.



> charmin plug


I never hear of this can you explain me this or some pictures if you can
Thanks


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## jimdoc (Apr 9, 2011)

PreciousMexpert said:


> Hi Emmjae
> How do you incenerate the polishing dirt.
> Do you do it like Harold with gas and pass over it with oxygen or do you use a hot plate with strong heat.
> 
> ...



That is when the search box comes in handy.

http://goldrefiningforum.com/phpBB3/search.php?keywords=charmin+plug&terms=all&author=&sv=0&sc=1&sf=all&sk=t&sd=d&sr=posts&st=0&ch=300&t=0&submit=Search

Jim


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## PreciousMexpert (Apr 9, 2011)

Hi Mike & Jim
I have a better idea about what charmin plug is but there is still a bit of confusion.
http://images.google.com/images?hl=EN&biw=1024&bih=578&gbv=2&tbm=isch&sa=1&q=Charmin+plug+filter&aq=f&aqi=&aql=&oq=

Charmin is the tissue paper 
Lets say I wanted to filter my solution 
I have 5 filter papers and than I place a few sheets of charmin tissue paper over that
Is this right and how is the plug word connected to this.
Thanks


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## Barren Realms 007 (Apr 9, 2011)

You roll the tissue paper up tight and put it in the small neck of your funnel.


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## Sodbuster (Apr 9, 2011)

A cotton ball works too.


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## Refiner232121 (Apr 12, 2011)

I have the filtered dirt after heating in AR for about 6 - 8 hours
and before that I boiled in Hcl
I dont know if there would be any silver in the filtered dirt but I can always test with nitric and salt.
If there was silver there 
Can I just heat that in nitric 
or do I have to remove the HCL first
Thanks


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## qst42know (Apr 12, 2011)

> I dont know if there would be any silver in the filtered dirt but I can always test with nitric and salt.



No you can't. Exposed to AR any silver is now immune to nitric.


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## glondor (Apr 12, 2011)

The link on page 1, Palladiums post, is dead. Can it be fixed?


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## Frankk12 (Apr 13, 2011)

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



> The link on page 1, Palladiums post, is dead. Can it be fixed?


If this is the post than its not working 
Can someone give me the good link
Thanks


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## lazersteve (Apr 13, 2011)

Fixed.

Steve


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## goldnugget77 (Apr 13, 2011)

I have a 2 part question

1
I denoxxed my AR and cemented.
I did testing with stannous and I got pink color
I thought it was gold but I added more SMB and the color would not go away
does this mean I have Pt in the solution

2
how can I check the dirt that went through AR boil and filter for silver
Thanks


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## goldnugget77 (Apr 14, 2011)

There was also a reddish substance in the filter .
This was after I dennoxed the solution and was filtering to get ready for precipitation
Would this be platinum .
I don't know how much there was but what is the value of half a gram of platinum

Also if there is reddish color in the denoxed solution Is there a way to precipitate it 
or do I reduce the volume and put it in the stock pot
Thanks


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## Frankk12 (Apr 14, 2011)

Red and orange colors are the platinum group colors.

Since silver in AR is not going to react with silver than you can incinerate a small amount and than test with nitric


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## BusinessMan (Apr 18, 2011)

> Since silver in AR is not going to react with silver than you can incinerate a small amount and than test with nitric


I did that and a few drops of salts and there was no reaction
I hope I did this right


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## qst42know (Apr 18, 2011)

Frankk12 said:


> Red and orange colors are the platinum group colors.
> 
> Since silver in AR is not going to react with silver than you can incinerate a small amount and than test with nitric



Silver in AR forms silver chloride. A simple incineration doesn't return it to silver easily. It takes a long roast with plenty of soda ash to convert back to silver. GSP covered this quite a while back.

Orange red is also the color of a false positive jewelers rouge (iron oxide) and SMB might create. Steve covered that a while back as well.


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## goldnugget77 (Apr 19, 2011)

Hi qst42know
The solution A shows pink I am guessing that it is palladium or platinum


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## BusinessMan (Jun 25, 2011)

I had some jewers dirt and I followed the incenerating procedure explained by Harold and others.
The refining was succeful but something happened and I would like to ask the folks here and that is during inceration the stainless steel try started to peel and chunks of metal started to come off.
My question is this
A) was the try not stainless steel 
or
B) the dirt became orange and very hot and I am wondering if I heated the try to much and I used electric hot plate
Thanks


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## Harold_V (Jun 25, 2011)

You most likely used a pan that was clad in aluminum. It's usually applied from roughly half the height of the pan, then downward, and covers the entire bottom. 

I suggest you avoid such pans entirely, even those that are covered with copper. Stainless (typically) has its own peculiar color, a slightly yellow cast. Aluminum is quite white---easy to discern from stainless. 

Harold


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