# Help! Pleasse help w/ dental appliances



## Paige (Aug 6, 2007)

I had 4 dental appliances that had held teeth (which were removed). I put them in AR as they appeared gold and were heavy. I slowly boiled the AR so that I didn't lose any gold to fumes.

I diluted the mixture. 

I thought all nitric was gone as there were still undissolved appliances at the bottom.

Thinking there might be some PL, I added some Sodium Chlorate. It boiled over into my heating element, so I unplugged it and dumped the solution back into my big solution.

I added a ton of SMB (I guess the nitric) was not all gone.

I poured the sauce into two jugs and filtered it.

The undissolved gold stuff turned a bright yellow and some pieces are now a gray metal.

I hit it with stannous chloride and it turned dark black.

I think I got gold out (some was stuck to a blob of SMB) and rinsed.

I sprinkled ammounium chloride into the solution moving very slowly through the filters and it turned red.

WHAT DO I DO?

I have solution contaminated by rust from the heater.

My solutions all test black with stannous cholride.

Should I add zinc powder, drop everything out, and start over?

I am certain I have values, but they are other than gold and I don't know how to recover them, espcially with the rust I added after the boil over.

I would certainly appreciate detailed help. Make it like you're talking to a 3rd grader.

Paige


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## Harold_V (Aug 6, 2007)

It is my opinion that you used terrible procedures in this instance. 

Without seeing the material, it would be difficult to spell out a good process, but assuming all of it was yellow when you started the process, I would have suggested that you inquarted the entire lot before approaching any of it with acid. It would be safe to assume that it was roughly 70% gold, and inquart accordingly. You would then dissolve the inquarted material in nitric, leaving behind the gold and some of the platinum group. Because any platinum that may be present would be combined with silver, some of it would be dissolved along with the silver in the nitric process, but it would be recovered, along with the silver, on copper scrap. You would then process the undissolved metals with AR, filter and recover each element of value according to typical processes. You should insure that all of the silver has been removed by heating your solution and allowing it to work for some time. Do not use excessive acid. Allow heat and time to do the work. 

Do you have Hoke's book? All of this is well addressed there. 

If any of the alloys you speak of were white in color, a high silvery blue luster, there's more than an even chance that they (or it) contained nothing of value from the standpoint of precious metals. Such objects should be eliminated from processing, not combined with the process. They are a high temperature alloy, thus difficult to melt, and do nothing but consume your resources and contaminate the values if you process them with acid. When they are dissolved in AR, they yield a dark greenish black color of solution. If there is any color that leans towards reddish brown, there are values being dissolved along with the base metals. Allow them to boil long enough and the base metals will precipitate the values. changing the color of the solution. It's one way to eliminate unwanted metals when you find them mixed. 

Regards your questionable solution, recovering the values with zinc would be very acceptable, but move slowly, with small additions. It sounds like the amount of nitric you have remaining is considerable, so it will be very reactive. Once you have all the values down (test with stannous chloride), stop using the zinc, take up the entire lot with a few volumes of tap water and allow things to settle well. Decant the solution, then start over with a small amount of nitric, to dissolve anything that will dissolve. This solution will likely contain traces of platinum group, so don't discard it without testing for values. Work with a small amount of acid and insure that it is used up. Do this by heating your solution and allowing time for the acid to do its work. The undissolved metals would then be processed with AR after being separated from the solution. Do not discard anything without testing first. You'll find the platinum group will follow every process to some degree. 

While this sounds redundant, it's a way to dispose of the large amount of unused nitric, allowing you to start over without losing values. 

Harold


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## Paige (Aug 6, 2007)

Thank you Harold_V.

Paige

Nothing began as white.

I had it on a low boil for over an hour. I was using 5:1 HCL to Nitric.

As I said, I thought the nitric was gone................

I will go with zinc, slowly, on small batches.


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## goldsilverpro (Aug 6, 2007)

*FINISHED*.

I started writing this before Harold's excellent post. In refining, for each type of material, there are probably at least 6 different methods of doing things. These are good, bad, or stupid. 

Please note that both Harold's way and my way have been proven to work. It is best to learn every way of doing something and, then, you can think about what is the best way for you, based on the equipment you have, turnaround time, cost, profits, efficiency, safety, etc. I hate to admit this but, if I ever refine karat gold or platinum group from jewelry or dental, again, I will adopt some of Harold's techniques and incorporate them with mine. I only hope that he has learned some tricks from me, on things like the sulfuric cell.

Did you use real nitric or sodium nitrate? 

There is always platinum (from .5% to 8%) and palladium (from .5% to 2%) in dental gold. The amateur looks at the high numbers. The pro looks at the low numbers.

*The Main Problem -Silver*


> I thought all nitric was gone as there were still undissolved appliances at the bottom.


The silver in dental alloys can be quite high (3% to 24% - the average is about 12%). If the silver percentage is over 10%, it becomes very difficult to dissolve all the gold in AR. Silver chloride forms and it coats the gold. This is probably the gray color you now see on some of the metal. The silver chloride stops the action and that's why you thought there was no nitric left. From here, everything snowballed. It takes both hydrochloric and nitric to dissolve gold. If EITHER acid has been used up, the action will stop. So, excess metal on the bottom does not necessarily mean that all the nitric is gone. It could mean that the hydrochloric is all gone and there's still excess nitric.

You should of inquarted, mainly because you must deal with the very possible high silver content.



> Thinking there might be some PL, I added some Sodium Chlorate. It boiled over into my heating element, so I unplugged it and dumped the solution back into my big solution.
> 
> I added a ton of SMB (I guess the nitric) was not all gone.
> 
> I sprinkled ammonium chloride into the solution moving very slowly through the filters and it turned red.



It was a mistake to add any of these chemicals before taking care of the nitric. However, it is less of a problem than you might think.

*How I would have done yellow Dental Gold.* I am using real nitric acid.

All of the techniques not covered in detail are covered in detail elsewhere on this forum.

*INQUART*

*(1) Weigh the metal*

*(2) Inquart with silver or copper.* First, though, calculate the copper or silver you need to end up with 25% gold. Make sure the molten alloy is well mixed before shotting. Stir with a carbon or quartz stirring rod (jewelry supplies).

*DISSOLVE THE COPPER, SILVER, ETC. IN NITRIC*

*(3) Estimate the amount of nitric nedded to dissolve the Ag.* One gram of copper needs about 4.2 mLs of concentrated nitric. A gram of silver will need 1.2 mLs.

*(4) Put the metal into the Pyrex dissolving container.* You could use plastic and no heat but, it's slower. For small amounts, I prefer glass beakers so, I can heat them.

*(5) Cover the metal with distilled water, plus about 1/4".*

*(6) Heat the solution until you first see whisps of steam coming off.* I like the hot plate about medium. Medium low for very small amounts

*(7) Measure out the calculated total amount nitric you'll need.*

*(8 ) Dissolve the Ag, Cu, etc., with nitric.* Add about 5 mL of straight nitric. You will immediately get action. It will shortly (few minutes) slow down. Give it a gentle but complete stir. It will flare up a little bit. Let it relax. Add some more nitric. When it's finished, add some more. Repeat until all the the Ag, etc., is dissolved and you only have gold powder. Test this by dragging the powder to the side of the beaker and looking at it. You can, also, mash around with a stir rod, to check for lumps. You may need about 10%, or so, extra nitric. Try not to use too much. This whole thing should take 15 to 30 minutes. The reason to start with only 5 mL, is to prevent it from foaming over. The solution will get quite hot from the dissolving and, you have to be careful of instant foamovers. Towards the end, you can progressively add more nitric at one time. But, never add more until the last addition has died down.

A good reason for working with heat is to eliminate foamovers. When you add a little nitric to a cold solution, it, at first, won't do much. You add a little more and, maybe, a little more. As you've been doing this, the dissolving action is heating the solution up, slowly. When it reaches a critical temp., it suddenly all works at the same time and, boils the solution over. Don't ask me how I know this. Most boilovers are caused by working with cold solutions or, by dumping all the acid in at the same time.

You will probably need more water, as you go, to keep the metal salts from crystallizing. At the end, you want to end up with 50% water. Stir.

*(9) Allow to cool and settle over overnight.* I like to prop a piece of wood under it, so the solids settle to one corner.

*Note: Summary of what we have to this point.* It's good to figure out what is where, no matter what you're working on.. 
----*(a)* In the solution, we have all of the silver, palladium, and all the base metals. If we used silver to inquart, instead of copper, we will also have some platinum in the solution. 
----*(b)* In the solids, sitting in the solution, there is most or all of the platinum and all of the gold and, some dirt.

*(10) Separate the solids from the liquid.* You can filter and rinse it or you can pour off the solution with several rinses - pour off - rinse - settle - pour off - repeat. For the best chance at good final purity, filter and rinse well.

*DISSOLVE THE GOLD AND PLATINUM IN AQUA REGIA*

*(11) Put clean solids in beaker.* 

[/b](12) Cover solids with the muriatic or hydrochloric.[/b] You should calculate how much HCl you need and add about 20%. For one ounce of gold, figure about 120 mL of HCl. It's very important to have extra HCl. But, it's wasteful and more cumbersome to add way too much.

*(13) Heat on medium until you see whisps of steam*

*(14) Calculate and measure out how much nitric you'll need* Figure about 20-25 mL, per ounce of gold. Measure on the low side. The goal is to never add any more nitric than is necessary to dissolve the gold and platinum powder. 

*(15) Add not over 5 mL of nitric* Action will start immediately. When it dies down, stir it and add some more nitric. 

*(16) Repeat adding nitric until the gold/platinum powder has dissolved.* Add - wait until reaction slows - stir - repeat. This may or may not take all the nitric. Especially towards the end, allow the action to completely stop before adding more nitric.

*Note:* The magic of adding a little too much HCl and just enough HNO3 is that, when you finish, there will be none, or very little, extra nitric in the solution. Thus, boiling down or, adding urea, isn't necessary. The first addition of SMB or FeSO4 will start dropping gold!!! If, you used too much nitric, use urea, that you've dissolved in water, until you get a pH of one.

IMPORTANT: Gold in powder dissolves rapidly. If you add too much nitric, the solution can foam over, quicker than you can say Jack Spratt.

The depth of the solution will make a difference in the speed of the dissolving. The deeper it is, the slower things go. The acid is way up here and the solids are way down there. For maximum speed, use a container that will keep the acid under about 3" deep. 

To kill or slow down foamovers, buy a small container of Anti-Foam located on the same rack as carpet cleaner rentals in the supermarket. Add 1" of the concentrate to a spray bottle and fill it up with water. Spray a little on the climbing foam. Often, it stops the foam. Sometimes, especially when real hot, it only slows it down. Believe it or not, just water in a misty spray bottle does a pretty good job on foam. Another weird way to to put a little oil on you fingertip and wipe it around the top edge on the dissolving container. I don't like oil in the solution. It tracks over to the next processes. I only use it rarely with large amounts of acid when no values are in the solution. 

*(17) Heat more strongly at the end but, don't boil.* Platinum dissolves a little slow and needs some heat.

*(18 ) Check to see if everything's dissolved.* Tilt the beaker, stir the solution, let it settle a bit, and, using good light, look at the settled solids, if there are any. If the container is small, pick it up and look at the bottom.

*(19) If needed, add more nitric.* Heat it up and add only 2 or 3 mLs at a time. Let it settle totally down and stir before adding. Keep checking for solids. Don't add too much.

*FILTER AND RINSE*

*(20) Add 3 times water and let it cool and let the dirt settle.*

*(21) Filter* Carefully pour the solution into the filter. Keep the solids in the beaker. When all the solution has drained through, rinse the solids (dirt) into the same filter. If things slow down, get a fresh filter.

*(22) Rinse the filter well.* 

*DROP THE GOLD*

*(23) Choose a precipitant.* There's a long list of things you could use: Ferrous Sulfate; SO2 gas; Sodium Sulfite; Sodium Metabisulfite; Sodium Bisulfite; Oxalic acid; Sodium Nitrite; Hydroquinone; Metol; Etc. The last 4 are only used in special situations. For this job, I should (but, probably wouldn't) first use green Ferrous Sulfate (FeSO4 - Copperas). It will drop the gold, without dropping the platinum group, better than any other precipitant. I could use a sulfite first and then melt, shot, re-dissolve, and final drop with ferrous sulfate. 

*(24)Drop the gold* To drop with one of the 3 sulfites, put a couple of spoonfuls in a one cup Pyrex measuring cup. Fill with hot water and stir until most is dissolved. Pour some of the liquid into the solution, let it react, and stir. If all of the nitric is gone, you should see brown powder forming in the solution. If there is still nitric, the sulfite will react with it before you start dropping gold. Sometimes, there is a false indication of gold dropping. The gold drops locally, where you added the sulfite but, when you stir it, the gold re-dissolves.

At some point, all the gold has dropped out. It shouldn't take much sulfite, if all the nitric was gone. Also, with no nitric, you should get no boilovers. Maybe, use about ounce for ounce, with gold or, a little more. There are some visual indications of this. Without the presence of platinum group, the foam (when stirring) will get white and the yellow color will disappear. With platinum, whose solution is also yellow, this is harder to see. Test the solution, with stannous chloride, for the presence of gold. Add a little more sulfite, stir, and test. Repeat until the gold is out.

*(25) Filter, leach and rinse the gold.* This has been a controversial subject between Harold and I. I would probably settle first, then, - (a) Filter the tops - (b) Filter the gold in the same filter - (c) Rinse 5 times with very hot water - (d) Remove and boil in HCl - (e) Filter and hot rinse 5 times - (f) Check for the presence of chlorides coming out of the filter, with a drop of silver nitrate made from a little silver dissolved in a little nitric/distilled water - (g) Rinse until no more chlorides - (h) Mix up enough 25% nitric, diluted with hot water, to pretty well fill up the filter. With a vacuum filter, shut it off and bleed the vacuum, first. The slower it drains through, the better. - (i) When it is drained, rinse 5 times with hot distilled water. - (j) Add 50/50 household ammonia, cut with hot water, and put it in the filter. When it has drained through, rinse 5 times with hot water. (k) Rinse 5 times with hot distilled water.

*(26) Dry the gold and melt it.* Look for instructions on the forum. Note: if the gold powder looks grayish, it has platinum in it.

*(27) Rework dirty gold* If the melt, the ingot, or the powder looks dirty, it is dirty. Pt makes dirty looking powder and ingots. Sometimes, the Pt.Gp. produces a fern-like pattern on the gold ingot. Always melt and shot the powder before re-dissolving in aqua regia. Use a different precipitant. Learn to use ferrous sulfate.

*GRAND SUMMARY*
---In the *filter papers*, there is likely some precious metals. If you can, keep the gold, silver, and Pt group all separate. Even if the platinum group filters have gold, keep them in the Pt. group pile. You can burn the filters or, you can add some of the best aqua regia filters to the next batch, paper and all. Don't add too many papers, unless you have a lot of solution. The hot acid pulps the paper and aids in filtering. Commercial paper pulp can be purchased for use as a lab filter-aid.
---*The spent aqua regia solution.* It contains platinum, hydrochloric acid, nitrates, chlorides, sodium, and sulfite. You could drop the platinum out as a black powder with copper buss bars (A trick. If it isn't cementing onto the copper, add a small shot of nitric and stir it in). Or, you could put it into Hoke's stockpot.
---*The nitric solution* It contains silver, palladium, some of the platinum, copper, zinc, and nitrates. How do you separate the silver from the platinum and palladium? Good question. You could drop the silver, Pt, and Pd, all together, using copper bussbar. You could then melt and run the silver through a silver cell. The platinum doesn't dissolve and stays in the cell's filter cloth. The palladium dissolves and eventually contaminates the silver cell solution. Another way would be to try and drop out the Pt.Gp., selectively, using something like hydrazine sulfate at a certain pH. Maybe, sodium borohydride would drop the silver without dropping the Pt and Pd. Anyone have any other ideas?


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## aflacglobal (Aug 6, 2007)

Great addition to my book. Great post Chris.


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## jimdoc (Aug 6, 2007)

Chris,
In #2 inquartation, do you use 25% of the precious metal content,
or just the gold. Considering it was dental gold do the other metals
affect that percentage for inquartation? Jim


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## Paige (Aug 6, 2007)

Thank you to everyone trying to help me.

I am not able to inquart as I don't have a torch. I have relied on a good friend to melt my final products - Steve Spevak. It sounds as though a torch is as important as the acids.

I use real nitric.

I have never had a problem with karat gold - except 10kt. It crusts over with silver.

None of my mess this time crusted over with silver.

Chris, you said 6 ways to do everything: good, bad, stupid; is that leaving (4) really stupid, (5) unbelieveable, and (6) let's boot him from the forum? I guess I fall into 5 or 6.

I surmise the one thing I did right was not throw anything out even though the thought crossed my mind. I would estimate that I have about 1 quart of liquid mess.

This was the big dental work that someone had in their mouth holding 8 false teeth. The teeth were gone. Each piece was very heavy, and I thought it had gold, PT and/or PL.

I use beakers and a hot plate. (Glass stirrers and separatory funnels are also in my list of equipment.) I took the beaker off the hot plate and held the beaker I was using up and saw these remains in the bottom. They were gold. I added a piece of gold to see if it fizzed and it did not. I thought the gold had used up the nitric and I had used 1:5 nitric to HCL. I heated it slowly so as to not boil off gold. After an hour, gold in the bottom, my dropped gold did not fizzle, I thought the nitric must be gone. I have the Hoke book. 

So I am less than an idiot with a lot of spilled milk. (No need to cry...)But after this disaster, I may give up refining; some people have the needed intuitions and I obviously don't. My contributions to the forum run to "what not to do." You are a great bunch of people. I appreciate the helpful suggestions that you are devising tonight and will follow through with them, Chris.

Paige


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## aflacglobal (Aug 6, 2007)

Hey, we all had to learn somewhere.

You don't even want to hear a Aflac story of some of my not so smart exploits.

Mistakes are how you learn. Hang in there. :wink:


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## lazersteve (Aug 6, 2007)

Paige,

Lighten up on yourself, we all learn from our mistakes. Dental gold is a big unknown for me aside from what Hoke and the forum members have written on the subject. I agree with Harold and Chris... inquart all higher karat gold items no matter the source material. I've had great sucess with inquarting. It's the only process that still ties me to nitric acid, but is also the best to separate base metals and silver from higher PGMs and Gold. If properly purified gold powder will melt fairly easily using MAPP gas. You should invest in a good torch and several melting dishes and molds. 

These items will make your life much easier. Separating the gold from the base metals before dissolving the gold will also make your life easier. As Harold has stated on numerous occassions, dissolving gold and base metals all in one shot and dropping the gold from the solution is like like taking a bath in muddy water. By removing all the base metals first, you have a much better idea of where your gold is and what a precipitated powder contains. 

Keep your chin up and take good notes on what Harold and Chris are saying. Inquarting works and works well. You already have the nitric you need. The silver is recycled in the inquarting process. Your gold will drop much cleaner and faster when the solution is not polluted with base metals and silver.

Keep us posted on your progress and don't give up. :wink: 

Steve


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## goldsilverpro (Aug 6, 2007)

> So I am less than an idiot with a lot of spilled milk.


The reason I know these things is because I have made all the same mistakes. The important thing is to try and not to make them twice.



> None of my mess this time crusted over with silver.


I assume you stopped dissolving because there was no action. You know there was lots of nitric left over - look at how much SMB you added and, still didn't drop the gold. Therefore, the only ways the action would stop are: (1) You ran out of metal; (2) You ran out of hydrochloric; (3) The silver chloride coats the metal; (4) The solution is too cold. With this new information, I would guess that (2) or (4) is the answer. I think you ran out of hydrochloric.



> I surmise the one thing I did right was not throw anything out even though the thought crossed my mind. I would estimate that I have about 1 quart of liquid mess.


You're right. Many would have trashed it. It's going to be easier than you think to sort things out. As long as you've saved it, we can get it out, in proper order.

If there's anything else you've forgotten, please tell me.

If refining were easy, everybody would be doing it.

*Some suggestions.*

Know all the numbers.
At all times, know where the precious metals are located.
Learn what different chemicals do to different metals and other materials.
Learn what heat does.
Know what's in the solution and in the solids.
Weigh and measure everything until you know more.
Keep records.
Add acids, precipitants, and urea in increments.
Study.
Know your options as how to process materials.
Don't re-invent the wheel.
Look before you leap.
If something goes wrong, don't go any further, until you've figured out what is wrong.
Never get cocky.


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## goldsilverpro (Aug 7, 2007)

Still not finished. Have added to my above post. Getting there. Tomorrow.

Jimdoc,

I'd probably just base the inquartation on the gold. It doesn't make that much difference. If you use too much copper or silver, for inquartation, the remaining gold can be very fine, slimy, hard to settle, hard to filter, and hard to rinse, especially if you use copper.


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## Paige (Aug 8, 2007)

Chris,

Many thanks to you for the instructions. I should add that I have about 1 oz of solids left and about a quart of liquids-mess left. Most of my values are tied up in the liquids. Can you give me more help with the liquids. Oh, I see that is coming tomorrow.

I also filtered the mess. The paper has dried but I feel the papers have values in them Would you mind adressing those. I don't want to gop the stock pot method.

Doesn't copperas add something to the mix?



Thank you,

Paige


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## goldsilverpro (Aug 8, 2007)

If there's anything you haven't told me about, if I've forgotten something, or if I'm mistaken about something, tell me. Stop and let me know if anything weird happens.

You have the solution, the solids and the filter paper.

*The solution* contains nitric acid (maybe), hydrochloric acid, gold, platinum, palladium, copper, NH4Cl, SMB, sodium chlorate,dissolved rust, and water.

I don't think the chemicals you added will hurt. They've all been chewed up and simplified by the acids. There is likely no SMB left. Dissolved iron won't hurt.

I would settle and then filter the solution. Then, treat it as a brand new solution.

(1) Filter and rinse.

(2) Take care of the nitric, if any. It sounds like there could still be nitric in there. I would dissolve some urea and add a little bit and stir it in. Normally, if you need more urea, you will get bubbles. After all the other stuff you've added, who knows? If you have a way of measuring pH, add til the pH goes up to 1.

(3) Drop the gold. You can use ferrous sulfate or a sulfite, such as SMB. Both Harold and I have only used ferrous sulfate a few times. However, Harold probably remembers more about it than I do. Neither of us like it much and, it is more complicated to use. The Hoke book covers it in great, great detail. Ferrous sulfate is more likely to keep Pt.Gp. out of the gold, thus producing higher purity gold. A definite advantage, in your case.

Depending on how much Pt.Gp. was in the metal, the more likely you'll have to rework it again, if you use SMB. Make sure you dissolve the SMB first, in hot water. Add a little at a time and stir between additions. When all the gold is out, stop.

(4) Filter, rinse, and leach the gold.

(5) Get the Pt and Pd out of the solution. Put some lengths of copper bussbar in the solution. In your small lot, use pieces of copper sheet. The Pt and Pd should produce a black deposit on the copper. If nothing happens, after about 30 minutes, add a splash of nitric and stir it in, to get things started. I would leave it for a couple of days. With a lot of Pt.Gp. is present, the heavy black powder can slow or stop the action. Just scrape and rinse it down and put the copper back in. When finished, scrape down the copper and collect the black powder. There will also be some black powder on the bottom of the solution. I would save this powder up and do a Pt.Gp. aqua regia later on.

*The Solids.* You have gold, Pt, Pd, Ag, Cu, and Zn in the metal alloy. You also have silver chloride and dirt. I would first rinse, dry, and get a weight on the metal left over. Then, calculate how much acids you'll need. See previous post.

In the following, I am assuming that what you said is true, about no silver chloride building up on the metal. If there is and things slow down, you may have to remove it once or twice and boil it in household ammonia, to dissolve the silver chloride.

(1) Cover the gold with whatever HCl you've calculated. You want a little excess. Put into a beaker that is at least 4-5" tall

(2) Heat til slightly steamy.

(3) Add some of the nitric (about 1/3) of what you've calculated and measured out. Drive it hotter. Heat is very important in aqua regia, when dissolving solid gold alloys. Don't boil. When the reaction stops, stir, add another 1/3 more nitric. Add the final 1/3 in smaller increments. You may not need it all. When a small addition produces no action, you should stop adding. If you didn't have enough HCl at the first, add a slight excess and see if it starts working again. If if does, you're not finished. If it doesn't, all of the metal should be dissolved.

(4) Dilute 3 times with water, cool and settle.

(5) Filter, etc., as in (1) though (5), above, in this post.

*The Filter Paper* You can save them up and burn to light gray ash, melt, shot, aqua regia. I have, before, dissolved the ash directly in aqua regia. Takes more acid and is a mess but, it works.

After the metal is dissolved and, before diluting with water, you could add the papers to the hot aqua regia. In your present situation, I would definitely do this. You may need a smidgen more nitric.


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## goldsilverpro (Aug 9, 2007)

Harold,

Surely, you could again comment on this thread. I would look forward to it.


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## Harold_V (Aug 10, 2007)

Chris,

I've spoken my piece, and it's now time for me to remain silent. 

It's dead easy to recover from his small dilemma, but at this point what Paige needs is one set of instructions that do not conflict with any others. Finding one's self in the middle of such an ordeal is not the right time to discuss the pro's and con's of the advice of two refiners that do not agree on procedures. Anything I'd post would eventually yield conflict. Albeit friendly between the two of us, it would be all the more confusing for Paige. 

Perhaps after Paige has resolved this batch, I would be willing to give precise steps in how I'd handle the same situation. He need not disclose what he did, only make a statement that he has finished to his satisfaction. At that point I'll expound on two different processes from which I'd pick were it my situation, assuming you'd be interested. Please ask if that be your desire, otherwise I'm finished with this problem. 

As you know, I'm very keen on inquartation (with silver). I would not make any recommendations that did not include that step, particularly where dental gold is involved. 

I would comment on one thing you said in your instructions. When one processes dental gold that contains platinum, the ratio of platinum as compared to the gold is so small that the platinum is finely divided enough that it does not take any longer to digest than does the gold. Further, a good portion, if not the majority, will already have been dissolved by the nitric process prior to the AR dissolution, so there isn't all that much present. The only way you know there's platinum present is by testing the solution. It never shows itself otherwise. 

Dental alloys were a large part of my refining experience---so I was quite comfortable with the process. 

Harold


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## goldsilverpro (Aug 11, 2007)

I agree 100%, Harold.


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## Palladium (May 5, 2008)

If your wondering what i am doing i'm reading old post for the Gold Refing Forum Handbook Vol # 2 ( soon to be release :wink: )


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## Rag and Bone (May 5, 2008)

Thanks for dredging up some good posts, Pd.


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## viacin (Nov 16, 2008)

Perhaps I can dig it up once more. I would like to see Harold's guide on the process. Surely Paige has finished the batch by now


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## twhittaker67 (Jun 18, 2017)

This is not so much a reply as a cry for help because I have the similar situation as the dental gold person. I have a huge amount of dirty aqua regia. (Yes I am a first timer and seem to have hit ever moron base as I rounded the field). I am begging for your help please. My AR is dirty because I disolved several processors, chips, pins, and trimmed Sims cards in my AR. I also have dissolved at least six very heavy gold rolled necklaces, and one solid gold septine necklace when first testing the AR's strength. Like the person on the previous post, I underestimated the strength of the nitric I had left. I added a total of four pounds of SMB to the the three jars I had(each over a gallon. I stirred the SMB to ensure as much contact as passible, as I stirred the solution was was a brown color but as th SMB settled it be came a bright yellow color with large pieces of gray/black metal. I filtered all the liquid off leaving the funnel and filter filled with this bright yellow goo. As I poured the liquid acidic smoke/vapors would rise from the funnel. The smell was much more pungant than AR. Ever after I completed the filtering, the yellow goo was very irritating to my fingers as I handled the filter. This was my first attempt and yes I know I made moron mistakes. You can make me feel ant stupider than I already do. Can you please help me. Did I drop any gold at all or just create highly acidic yellow goo and over two gallons of waste acid in my bucket? Is there any way of salvaging this mess I made. Can you please help a newbie when you get done laughing?


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## FrugalRefiner (Jun 18, 2017)

twhittaker67 said:


> Can you please help a newbie when you get done laughing?


There's nothing to laugh at. You have made some mistakes, but safety is the first rule.



> Ever after I completed the filtering, the yellow goo was very irritating to my fingers as I handled the filter.


Wear gloves! Everything we deal with is toxic. Safety first!

Dave


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## twhittaker67 (Jun 18, 2017)

Dave:
Thank you for not laughing. You are right. Saftey should aways be first. Can you please help me or do I just have 2.5 gallons of waste that will forever have elemental gold trapped in it. Please help can I still use copperas or smb to drop the gold from my solution. Please any advice at all is welcome.
Thank you for anything you can do.
Terry


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## g_axelsson (Jun 19, 2017)

Not laughing, just shaking my head in disbelief. At least you realized the problem and made the most important step to seek help.

As Dave pointed out, safety first! Dissolved metals can be absorbed through the skin so no more handling the acid products without gloves. And don't breath the fumes! I hope you did your experiments outside and not in a closed room.

Read this after you have read up on safety. http://goldrefiningwiki.com/mediawiki/index.php/Making_a_mess (including the links at the bottom).
Next you should also read up on waste treatment.

And remember, if you get some scolding it's not because we are mean, we just want you and people around you to be safe.

As long as you don't pour out any liquid or throw away any solids any gold you started with is still there, it's just a matter of finding it and extracting it.

You mentioned a number of stuff you put into your aqua regia, can you put some numbers on it like kilos, number of CPU:s, liters of HCl and HNO3 used... (or pounds, oz or the like). That way we might get a better picture of your mess.

Don't panic, there is no rush to test a lot of stuff. Do any testing with small amounts and if it works then you can start treating the bulk. And test, test and test with stannous to follow your gold.

Göran


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## twhittaker67 (Jun 19, 2017)

Thank you for all of your advice and tolerance. Rest assured I work outside and will always wear proper PPE from now on. I should have never ventured into this. Impatience and refinement do no mix. I see that now. I had about 20 processors,20-30 chips that had gold in them, 35MCC (which gives me a platinum problem) 6 very heavy gold filled necklaces, and one solid gold necklace that I added to try and denos before giving up, realizing my total screw up. I have added a total of 6 lbs of SMB and after filtering all I have is bright yellow powder. What is that by the way? Just a waste by product of the smb? Please any further help you are willing the share woul be a Godsend. I tried a stannis test but with homemade stannis (95/5) solder and HCL. I got no result but with my record if success so far I ordered stannis chloride from a chemical company. Please tell me what the yellow goo is (lol) and should I do anything but wait for the stannis to test? I read the link you sent and am reading more now. Please help.


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## FrugalRefiner (Jun 19, 2017)

Relax. Until you throw something away, you can't lose your gold.

As a guideline, we usually use about the same weight of SMB as we're expecting in gold, so unless you were expecting 6 pounds of gold, you overdosed on SMB. That's probably a lot of your yellow goo, mixed with the gold that probably precipitated and the base metals you also precipitated by the overuse of SMB.

When your stannous arrives, you can test the solution, though I feel confident there is no gold in there. Spend your time studying until it arrives and you'll be better prepared to use it. If you haven't already done so, I recommend downloading the book in my signature line. It will answer a lot of questions you don't even know you have yet.

Dave


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## twhittaker67 (Jun 20, 2017)

As a newbie and a YouTube addict (don't boo) I forgot the the first rule of high school science. Study ten hours for every one hour you are going to experiment. My impatience and lack of belief if I can't "see" it work against me. 
Am example was the HHO generator I built that produced no bubbles in the water blaowback valve. Yes I do practice saftey. That is until that old devil frustration whispered " listen to your teenage son" when he said he dad hold the grill lighter to the hose's end. The sound was not unlike a .45 being fired under the hood of my explorer and I spent hours sweeping up glass. The unsafe behavior did prove without a doubt that I was prove I produced hydrogen and oxygen and that the bubbles on YouTube were exaggerated for the camera. I now have one way valves and redundant anti blowback system and my 21 year old Ford averages 40 mpg. Having said all that. From the "instructive" videos smb was to be added until the solution no longer fizzed or was "denossed" apparently I had created a super nitric solution. The green color was not due to copper content. I have made many mistakes but I have learned to take every proper step (removing base metal etc) no matter how big my hurry. OBEY ALL SAFTEY LAWS (no matter my curiosity) I could not understand the extreme acidic smell of my yellow "goo" nor th "slimey" feel through the gloves. Hence I foolishly took off my glove and discovered this paste was as acidic as my solution, plus the first time I added small amounts of smb there was no measurable precipitate. My intention was to drop everything from solution and start from scratch. I have learned 3 S,,'s are basic to the refining 1. SAFTETY, 2. STEP (FOLLOW EVERY STEP), 3. STOP/ SEEK ADVICE. Marching forward without pause leave one with 2.5 of corrosive hazardous waste to dispose of. AND NO GOLD LOL.


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## FrugalRefiner (Jun 20, 2017)

twhittaker67 said:


> From the "instructive" videos smb was to be added until the solution no longer fizzed or was "denossed" apparently I had created a super nitric solution. The green color was not due to copper content.


It's not "denossed", but deNOxed. When nitric acid breaks down, a number of compounds can result, such as NO, NO2, etc. We group them all together with the term NOx, where the x represents the number of oxygen atoms in the compound. We need to get rid of these compounds, so we deNOx the solution.

A number of metals can create green solutions. Color is not a reliable way to determine what is in solution.

Dave


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## anachronism (Jun 20, 2017)

I think you also forgot the first rule of paragraphs.


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## twhittaker67 (Jun 21, 2017)

I guess I can chalk this up to beginner's luck filtered out all solid
Stannis test was negative for gold in solution. Allowed "golden goo" and all filters to dry. Started from scratch removing metals with HCl. Dried all filtered powder. Added to clean proper AR. Dropped once more with smb. Filtered, dried and torched with borax as a flux. Dropped in water bucket resulting in a button that was 48 grams of 24k. Already tested and bought by the local "ee buy gold shop" I think I will retire from this never racking hobby. Gonna by s Sig that I have drooled over for months now. At least at the range I know what I am doing. Good luck to you all.


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## g_axelsson (Jun 22, 2017)

Not laughing at you now either, just smiling for a story with a happy end.  

If you ever want to continue learning refining you know where we are. You have already refined gold once, second time is easier. :wink: 

Göran


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## Topher_osAUrus (Jun 22, 2017)

What did the "we buy gold shop" pay you for that hefty chunk of gold, if I may ask?


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