Stannous chloride Colors?

[ikielee]

Hello all
I am new to this and am starting to see some results thanks to the help of this site and hokes book.
one thing that baffles me is that when i am sure i have completely dropped out all i can i still test positive for something, and
i am stuck keeping that solution , afraid to throw away any thing of value. I am working mostly with gold filled scrap
i have gotten pretty good at gauging the amount of gold to expect and in most cases am withing 1 gram either way. I use sodium metabisulfite
to drop the gold and the above stannous chloride to test.
in the scrap i am handeling i cannot see there being any platinum or paladium but i get a brown test at the end.(very brown) when left to sit it precipitates as a black powder and when more stannous is added it globs up floats to the top and begins to dissolve to brown again.
what is this. I admit i use more smb than i probably should to drop the gold. would this give the brown test results.
I also have added more smb to the solution and have dropped a very very small amout of gold but mostly when melted the metal i get from the second drop resembles silver (or lead , or murcury) as when i disslove it in AR it forms a white covering. still these metals dont give a positive test in stannous do they.
and even though i am adding what should amount to too much smb the solution still will give a brown test.
I have litterally gallons of this excess solution i am afraid to dispose of do to these test.
any help would be appreciated and i would like to thank all on this site for the help i have allready recieved.
ike

 

[butcher]

Keep reading in Hoke's book she addresses your question in several manners, like keeping a healthy stock pot, cementing useing metals like copper, and testing for metals in solution (also those which can fool you into thinking you have something of value like iron).

Are you sure the brown reaction is not a false positive reaction caused from the use of too much SMB?

 

[ikielee]

i was thinking it was the SMB , so i set up a test
and it didnt show the brown.
also i negleted to mention that i am disolving all base metals with nitric (home made)
and disolving the gold in hydrochloric acid and clorox bleach. so as i said i made some of this and mixed in the SMB
again no brown , however i didnt disolve any thing in it either.
the items i am working with have iron, i am sure but i cant see the amount i am testing at getting by the nitric treatment.
the fact of the matter is
i got my gold i was expecting
i need to just consider the rest for what i am sure it is
trash
thanks for the eye opener
ike

 

[Palladium]

All you have to do is put a piece of copper in it for a couple of days. It's their are any precious metals they will attach to it and fall off. That's how you get that last bit out. That's your fail safe when you aren't sure.

 

[CampB]

Back on Nov 28th 2012 I contacted a good member of this forum and asked about getting a positive read from a 30%/70% Nitric bath of PM's. Since then I've learned more about my getting a positive Stannous read for Au from my 30%/70% Nitric bath after parting beads with Ag, Au, and Pd in them. As a result I now have more questions. What we have concluded is that the Au is still attached to my Pd on a molecule state and that's why it shows purple in Nitric.

My question is what's the best way to separate Au and Pd from each other. I've read to keep re-refining with AR and that's what I'm working on but that's a long process. What does Pd like more than Au? What can I give it on a molecular level that will make it drop Au and run to _____? Has someone done it before? Is there a formula or procedure you have seen to do this?

Keep in mind I'm working with a complex ore and I'm testing anything and everything to find how to break this bond.

Any suggestions or help would be appreciated.

Thank you,
CampB
Dan

 

[solar_plasma]

Can SnCl2 be used for quantitative analysis in a spectrometer by comparing with known concentrations, given that there is only one kind of the metal ions, that give a positive result? I have a cheap one at school that only works with 3 defined wavelength (green, red, blue) of light showing the measured results on a pc.

 

[amosfella]

I have a solution that I'm playing with as a test on black sands from a platinum placer mine. I'm trying to figure out what I have in the solution before I get an assay done. I put a small handful of the sands into a bucket that I had a fire going in while I was trimming dead branches off the trees. There was a fair amount of yellow smoke coming out of the bucket for a bit, and I kept the fire going till long after the yellow smoke stopped. Then I had the joy of panning the sand back out of the ash (elm wood leaves a lot of ash). After that I put a few pinches of the fine sand into a small bowl and put some hydrochloric on it. It did have some brown in it, but not much the next day, so I added a small amount of nitric to it and heated it for about 5 min. Then I let the solution sit for a day. I came back to an almost burnt orange color of solution. It has silvery metalic looking fines on the bottom of the glass that I couldn't dissolve with AR.
I mixed up some stannous chloride, and I poured a few drops of the burnt orange solution into a very small glass bowl. Then I added stannous, and the solution turned bright canary yellow, and then went clear a few seconds later. When I went back after leaving it for about an hour, the solution was brown...
Now, I'm trying to figure out what I have.
The solder I used was 97% tin/3% copper. Any ideas what I have there??

Don,

I use this formula for making stannous and I always have the same results no matter what the source of the scrap is:

1) 2 grams of pure powdered tin
2) 30 mL 32% HCl
3) Heat until fizzing begins (this takes around 10 seconds depending on your heat source)
4) Stop heating and let react uncovered until the solution clears, the solution should be colorless.
5) Store in a sealed container out of direct sunlight
6) Undissolved tin should remain in the storage vessel at all times
6) Test against known PM solution once per week or when you suspect it is not working

Here's the photos of the positive swabs and the Rhodium stannous test:

and positive test of Rh (left vial) and Pt (right vial) in solution using heated stannous chloride:

Steve

 

[jonn]

CampB, you stated your AU is attached to PD and shows purple in Nitric. I wonder? When AG in Nitric is exposed to light it turns purple. You add HCL to drop your AG and then filter out your silver chloride that forms. Test your solution after your silver is out of the mix. If for some reason you suspect there to be gold , do a small test tube sample first this way and see your results. Otherwise you may be chasing AU that is not there. Let us know what it results, Jonn.

 

[Sunspot]

Hey guys, new to all of this but I am reading a great deal. I have a quick question about stannous chloride.

I understand this method is about making it from hydrochloric acid and tin. I actually have a container of stannous chloride, how would I use this to create a solution to test gold? Can I just mix it with water? I mean when you mix HCL and the tin you get a chloride salt and water right? So I imagine it's the same thing.

My only other question is how many grams of stannous chloride to how many ml of water. I did do a google search but couldn't quite find an answer.

 

[FrugalRefiner]

C. M. Hoke covers that in her book. There is a digital copy you can read on screen here: Refining Precious Metal Wastes. If you prefer a printed copy, you'll find a link to a printer friendly version in my signature line below.

Dave

 

[Sunspot]

I did scan through the book before posting this but all I found was a discussion of adding hydrochloric to tin, I guess I must have missed it, I'll have a better look thanks

 

[FrugalRefiner]

Chapter IX.

Don't just scan the book. Read it. Then read it again.

Dave

 

[Sunspot]

Chapter IX.

Don't just scan the book. Read it. Then read it again.

Dave

You're right. I'm going to spend the next week going over it. In fact I'm going to print it because I deal with things better in printed form. Thanks for your input, but despite my A level chemistry knowledge I have no doubt I'll be asking a few questions.

I'm happy to say I have the method for ceramic chips in place and now I understand the AP method for removing fingers from memory. I'm leaving the palladium from monolithic stuff and the flat pack stuff until I understand the processes.

Even though I have chemistry to a level I understand there are several processes which are quite involved, and for safety reasons I need to be careful.

I'm building a fume hood and scrubber, along with a secondary carbon scrubber. I'm starting with the simple stuff, fingers and ceramic chips. After that I'll need a lot more research.

 

[Sunspot]

Frugal refiner.

Thank you for your printer friendly version of Hoke. I've downloaded it and now throwing it at my inkjet

 

[FrugalRefiner]

You're very welcome.

As you study her book, remember it was written over 70 years ago. I'm reviewing it again, specifically looking for differences between what she teaches and procedures which are considered to be better or safer with our current knowledge. We've previously cautioned that one should not toss gasoline on while incinerating, taste their rinse waters, or pour untreated waste down the drain. I'll be adding more in the near future, such as not refining in the basement of your residence, and not using the word boil when your intention is to reduce the volume of a solution through evaporation.

Dave

 

[IdahoMole]

I made my first batch of stannous chloride per Steve's recipe. I put 2g of 95/5 tin/antimony solder, cut into small bits, into 100ml beaker and added 30ml of HCl. I did not use heat. After two hours the tin was dissolved so I decanted the solution off of the antimony residue into a plastic dropper bottle and added a small bit of solder. A short time later I notice there were a lot of bubbles coming off the solder. So I think to myself, bubbles equal pressure in the bottle and that's not good, must be too much free HCl. I then poured the solution back into the beaker with 4g of additional solder. I put the beaker into a coffee pot and covered it with a glass plate and left it over night. This morning the reaction was done so I decanted back into the dropper bottle with a new bit of solder. The bubbling has stopped and everything looks fine.
Was I correct in thinking that i should consume the free HCl before bottling to prevent pressure buildup and is my stannous still good considering I have about 5g in solution rather than the 2g called for?

 

[upcyclist]

I made my first batch of stannous chloride per Steve's recipe. I put 2g of 95/5 tin/antimony solder, cut into small bits, into 100ml beaker and added 30ml of HCl. I did not use heat. After two hours the tin was dissolved so I decanted the solution off of the antimony residue into a plastic dropper bottle and added a small bit of solder. A short time later I notice there were a lot of bubbles coming off the solder. So I think to myself, bubbles equal pressure in the bottle and that's not good, must be too much free HCl. I then poured the solution back into the beaker with 4g of additional solder. I put the beaker into a coffee pot and covered it with a glass plate and left it over night. This morning the reaction was done so I decanted back into the dropper bottle with a new bit of solder. The bubbling has stopped and everything looks fine.
Was I correct in thinking that i should consume the free HCl before bottling to prevent pressure buildup and is my stannous still good considering I have about 5g in solution rather than the 2g called for?

Your stannous chloride will last longer if you actually store it with an excess of tin in the bottle. So yes, absolutely use up the free HCl--that extra bead of tin left will tell you that you are done.

And yes, your reaction should be complete before you seal your bottle. I use the fillable dropper bottles, too--HCl will eat the black rubber on your traditional bulbed glass dropper bottle.

 

[upcyclist]

This morning the reaction was done so I decanted back into the dropper bottle with a new bit of solder. The bubbling has stopped and everything looks fine.

Your stannous chloride will last longer if you actually store it with an excess of tin in the bottle. So yes, absolutely use up the free HCl--that extra bead of tin left will tell you that you are done.

My apologies. I was multitasking instead of reading carefully what you had written.

 

[IdahoMole]

No need to apologize. Thank you for the reply.

 

[Barren Realms 007]

You will probably need to filter the solution.