# Dropping Gold using Stump Out (sodium metabisulfite)



## kadriver

Here is a short video I produced to demonstrate the technique I use to drop gold using Stump Out purchased from Home Depot (about $6 per pound).

[youtube]http://www.youtube.com/watch?v=HNq3Tp99XOE[/youtube]

I have gottten good results so far using this process.

Please give comments or suggestions if you see anything improper.

If dropping gold using this method will hinder the recovery of other PMs in solution, then I would like to hear about that as well.

Thank You - kadriver


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## Geo

nice video as usual.what was the weight on that powder?


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## kadriver

I got a bar that weighed 2.08 trot ounces. Thanks


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## Oz

kadriver,

I would suggest that when rinsing down your buchner funnel you use your spray bottle on fine mist instead of the squirt bottle you used.

A stream of water instead of a mist can lift up the edges of your filter paper allowing solids to bypass the wet seal of your filter paper.

Nicely done video.


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## kadriver

Oz:

Thank you for the tip. I noticed as I watched the video that the edges of the filter paper seemed to lift a tiny bit. 

From now on I will use a squirt bottle with the nozzle set for mist rather than a solid stream.

kadriver


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## TXWolfie

Kadriver thanx a bunch I was just looking up SMB on Wikipedia and it mentioned Stump removal products that contain SMB. So I was going to ask in the forum and I seen this video..... answered my question and HA HA no search box was used :lol: ....just wish I would of seen this yesterday since I was out in Lowes getting Muriatic  Guess I will go to Walmart since its closer.

Rich


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## kadriver

TXWolfie:

I have found Stump Out at Home Depot. I could not find it at Lowes. It may not be carried by Lowes.

I don't know about WalMart - if you find some there, then please let me know (Walmart is closer than Home depot).

Thanks - kadriver


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## philddreamer

Gentlemen, keep in mind that not all "stump out" products are SMB; the one by BONIDE is. Make sure you read the label.

I just read another post where someone bought stump out & it's potassium nitrate. 

Take care! 

Phil

P.S. I found it! :mrgreen: 

"2-Kadriver you also mentioned in an old post you found Stump Out at HD. That the Stump Out was Metabisulfite, did I read that wrong? I went to HD the other day and the product they had called (stump out) had Potassium Nitrate in it?
Thanks Kadriver,
Oneal58"


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## kadriver

The Stump Out I purchased at Home Depot is sodium metabisulfite. It is made by Bonide (as per the label). I verified this before I bought it by asking for and receiveing a copy of the MSDS from the Home Depot help desk at the front of the store.

I kept the copy of the MSDS on file at my shop. As I recall (I don't have it in front of me) it is in the upper 90's as far as purity is concerned.

As stated earlier in this post, there may be other "stump out" products made by companies other than Bonide. These other "stump out" products could contain other chemicals that are not suitable for refining gold.

To be safe, before you buy the stump out, ask the store to provide you with a copy of the MSDS to verify that it is sodium metabisulfite.


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## Barren Realms 007

Why is your stannous cloudy?


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## kadriver

Barren:

It has always been cloudy like this. The only time I have seen it not cloudy is when I first make it up. It stays relatively clear for about a week, then it turns cloudy like you see in that video.

That batch of stannous was made about 3 weeks ago from today. Is it possible that the solution has already gone bad?

I used this recipe:

25ml distilled water
1 dwt stannous chloride
1 dwt tin metal
30 drops hyrochloric acid.

Is there a different recipe that will give me a clear stannous test solution?

kadriver


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## philddreamer

I use 15ml of HCl & about 1.25" of 96% tin/4%silver from Radio Shack.

Phil


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## Barren Realms 007

kadriver said:


> Barren:
> 
> It has always been cloudy like this. The only time I have seen it not cloudy is when I first make it up. It stays relatively clear for about a week, then it turns cloudy like you see in that video.
> 
> That batch of stannous was made about 3 weeks ago from today. Is it possible that the solution has already gone bad?
> 
> I used this recipe:
> 
> 25ml distilled water
> 1 dwt stannous chloride
> 1 dwt tin metal
> 30 drops hyrochloric acid.
> 
> Is there a different recipe that will give me a clear stannous test solution?
> 
> kadriver



I don't think it has gone bad looking at your test results on your gold solution. Unless one of the pro's here see's a problem with it being cloudy you should be ok. I use HCL and 95/5 plumbers solder with no exact ratio to use, I just cust up some pieces of solder and put it in the HCL on a slight simmer. When it is done I filter the solution just put a few pieces of solder in the container and it last's me for month's of good use. If you want some of the solder send me a PM with your address and I will send you some to use.


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## 4metals

I make my stannous exactly like Kadriver does. I've been using stannous that gets as opaque as milk for years, it has a long shelf life if you don't expose it to too much air, I limit the air exposure by storing it in a dropping bottle that is kept closed tightly. 

The most important solution you can have alongside the stannous bottle is a small bottle known to have gold chloride in it so you can test your stannous when you get a negative reading. I always tell people to test their stannous when the first test of the day is negative, this way you know if the stannous is good.


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## TBarrow

4metals said:


> I've been using stannous that gets as opaque as milk for years, it has a long shelf life if you don't expose it to too much air, I limit the air exposure by storing it in a dropping bottle that is kept closed tightly.



I saw this in the Wikipedia article on Stannous Chloride:

"_Chemical propertiesTin(II) chloride can dissolve in less than its own mass of water without apparent decomposition, but as the solution is diluted hydrolysis occurs to form an insoluble basic salt:

SnCl2 (aq) + H2O (l) Sn(OH)Cl (s) + HCl (aq)
Therefore if clear solutions of tin(II) chloride are to be used, it must be dissolved in hydrochloric acid (typically of the same or greater molarity as the stannous chloride) to maintain the equilibrium towards the left-hand side (using Le Chatelier's principle). Solutions of SnCl2 are also unstable towards oxidation by the air:

6 SnCl2 (aq) + O2 (g) + 2 H2O (l) → 2 SnCl4 (aq) + 4 Sn(OH)Cl (s)
This can be prevented by storing the solution over lumps of tin metal._"

There seems to be a lot of discussion about the milky nature of the solution. I haven't made any with concentrated HCL only, but it seems that the Wiki article is suggesting this for a clear solution. I could be reading it wrong.

Todd


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## kadriver

The last batch of stannous chloride I made lasted for months in that it would give a reaction when applied to AuCl.

However, I did not have AuCl standard solution to test the stannous with!

I have just now learned this - I will make a batch of AuCl standard solution today. I may have been getting a false negative test with my stannous with no way to verify it's reliability.

I need a test solution for my test solution - what a concept.

I have a .1 gram sample of fine gold. I will disolve this in a touch of aqua regia then put the resulting AuCl in 100ml distilled water.

That should yield a solution of 100 milligrams gold in 100 ml of solution as recommended by Hoke.

It is amazing how I never stop learning new things here!

kadriver


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## RGJohn

kadriver said:


> It is amazing how I never stop learning new things here!
> 
> kadriver



Thank you kadriver.
It's amazing to me that you never stop teaching new things here.


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## TXWolfie

Ok I have a question does it really matter on how diluted the muriatic/clorox mix is before the SMB will not work. What i am referring to is I have a few bottles of an old mix of acid/peroxide mix that I used to take off foils. If I took out like an ounce of liquid and added clorox to do a test run and add smb to see if anything drops, will there be no affect if its too diluted. Or could I just drop some SMB into it to see if anything drops out. Just a litttle confused and dont wanna mess with it any further.


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## butcher

"Ok I have a question does it really matter on how diluted the muriatic/clorox mix is before the SMB will not work. "

Water in solution is needed to generate SO2 gas(chlorox, sodium hypochlorite has much water in solution), (HCl, hydrochloric acid has much water in solution) so unless you concentrated (evaporated off water) you have water in solution.

"What i am referring to is I have a few bottles of an old mix of acid/peroxide mix that I used to take off foils. If I took out like an ounce of liquid and added clorox to do a test run and add smb to see if anything drops."

I do not understand this?? why are you adding sodium hypochlorite to acid peroxide?? this makes no sense.
and then adding sodium metabisulfite?? and expecting to precipitate something???
either you wrote this wrong or have no understanding of the processes. 

"will there be no affect if its too diluted. Or could I just drop some SMB into it to see if anything drops out. Just a litttle confused and dont wanna mess with it any further."

Confused yes, do not add bleach or SMB to your acid peroxide solution, save it to reuse to dissolve more copper from under more gold plated copper foils, go back to Laser Steves web site and read some more, untill that lamp in your head lights up, also read about the process on the forum. have you read the general reaction list?


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## TXWolfie

Alright forget the first question I forgot I asked that a while ago and got my answer. I have seen a few video's that Lazersteve has done with using muriatic and peroxide to take off gold from fingers. I do have several glass bottles I am using to hold that fluid after I ran it thru filters. I attempted to make Stannous for testing but i dont think it worked at all, maybe I will try another batch. So I was wondering with those bottles I have sitting could I use SMB on them to see if gold will drop and pass thru the filter, with the small possibility that minute gold particles will be in the mix after I use some clorox per LazerSteve's concept. And the biggest real question of them all, How hot does that mix really get when your dropping gold has anyone took a temp of it I am just curious.

Rich


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## butcher

Use a copper buss bar, if gold is in solution copper will cement it out, leaving your solution in good shape for another batch.

Read Hoke's book.

She teaches you how to make a gold test standard solution. you can use to test your stannous chloride solution with.

Did I mention read Hoke's yet?


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## Richard NL

"just put a few pieces of solder in the container"
"storing it in a dropping bottle that is kept closed tightly"

Wrong combination!

Pressure will build up from the hydrogen gas.
The first thing that will expand is the rubber bulb, till the point it will rupture.
Blowing almost all the Stannous Chloride out of the glass pipette dropper bottle.

It was a real mess and a whole lot of cleaning.
Everything covered in Stannous Chloride


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## goldsilverpro

Richard NL said:


> "just put a few pieces of solder in the container"
> "storing it in a dropping bottle that is kept closed tightly"
> 
> Wrong combination!
> 
> Pressure will build up from the hydrogen gas.
> The first thing that will expand is the rubber bulb, till the point it will rupture.
> Blowing almost all the Stannous Chloride out of the glass pipette dropper bottle.
> 
> It was a real mess and a whole lot of cleaning.
> Everything covered in Stannous Chloride


The 1st time I made sannous chloride, I put it in a bottle with a rubber bulb/eyedropper, just like you. Same thing happened except I caught it before the bulb popped. It had expanded to about 2" in diameter.

When Hoke says, "dropping bottle", she's not talking about one with a rubber bulb. She's talking about a glass bottle with a fritted glass stopper. The stopper is turned to a certain position that allows drops to come out, one by one, when the bottle is tilted. Hoke wrote that book 76 years ago. When I first started, these bottles were very common. They still make them. The last touchstone kit I bought had 4 empty glass dropping bottles, with instructions how to make the acids.

http://www.coleparmer.com/Product/Clear_glass_dropping_bottle_50_mL_Pack_of_6/EW-08923-04


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## Richard NL

I hope that we can reduce this mistake by these posts!

The clear glass dropping bottles in the link you gave, looks really nice.
But a bottle with a rubber bulb/eyedropper can be purchased for about +-€1,25 (7 minute walk to the store)
I think that a newbie has a great chance to make the same mistake.


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## upcyclist

I use the polyethylene refillable dropper bottles--basically, you squeeze the body instead of a dropper bulb. In my experience, acids eat those bulbs like, well, acids eat them 

Also, with these, you can leave the cap on loose, it still protects the contents (contaminants would have to travel uphill to get to the opening in the bottle).

I got mine from amazon, but they're not too hard to find elsewhere.

--Eric


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## FrugalRefiner

Cheaper on eBay.

Dave


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