Stannous Questions

Gold Refining Forum

Help Support Gold Refining Forum:

CatGrl00

New member
Joined
Jul 22, 2022
Messages
2
Location
Ohio
Hi, I have read mixed information as to what colors show for certain metals using stannous chloride. If anyone would be willing to give their opinion on these tests I'd really appreciate it!
 

Attachments

  • Screenshot_20220722-075531_Photos.jpg
    Screenshot_20220722-075531_Photos.jpg
    359.1 KB · Views: 0
  • Screenshot_20220722-075449_Photos.jpg
    Screenshot_20220722-075449_Photos.jpg
    344.6 KB · Views: 0
  • Screenshot_20220722-075409_Photos.jpg
    Screenshot_20220722-075409_Photos.jpg
    472 KB · Views: 0

Yggdrasil

Moderator
Staff member
Moderator
Joined
Oct 30, 2015
Messages
2,065
Location
Norway
Hi, I have read mixed information as to what colors show for certain metals using stannous chloride. If anyone would be willing to give their opinion on these tests I'd really appreciate it!
Often tests are easier to read if you use paper strips or cotton buds, dipped in solution in stead of spoons, spot plates and similar.

Edit: spelling error
 
Last edited:

4metals

Moderator
Staff member
Supporting Member
Moderator
Joined
Apr 5, 2009
Messages
5,197
Location
northeast USA
The quick answer is lack of gold. But it is possible you didn't apply the stannous properly, I've seen that when stannous was dropped into a reaction and the result was diluted. So please, detail how you tested.
 
Joined
Jul 13, 2022
Messages
26
Location
Massachusetts
It is kind of complicated (and procedurally messy) so I will be terse. I am a beginner and I want to be respectful of your time, so here goes:

1) In several iterations, I placed a couple of pounds of circuit boards and assorted gold plated devices (with significantly visible gold) in a beaker and used the Shor International Product (I know it is frowned upon here) to create AR. All went well and I observed plenty of purple stained stannous tests.
2) I then used urea (I know, that too is frowned upon here) to denox. I still had plenty of purple stained stannous tests. Frequent filtering the solution is implied here.
3) Dropped the gold with their product (Shor Quadratic Precipitant). So far, so good....had brown mud at the bottom of the beaker.
4) Cleaned mud with ammonia and then distilled water (as they suggested). Now everything goes south...
5) I attempted to refine this accumulated mud even further using the same procedures above. This left me with approx 3 gallons of green AR with no precipitant and NO gold in solution - all negative stannous tests.
6) I added lots of SMB and no change.
7) I then added clean copper pieces to the 5 gallon bucket (hoping to cement out the gold) and after a couple of weeks, I recovered quite a bit of brown precipitant.
8) I HCL rinsed it (warm) and Distilled rinsed it (warm) until it was clear - and then dried the brown powder.
9) I used the Shor Product (a nitric acid substitute) one more time with 10 grams of this newly acquired power - then heated it about a hour.
10) Then this Stannous test went from dark brown to clear in 2 seconds.
11) I know there is gold in there and I do not want to discard it.

Thanking you all in advance....
 

4metals

Moderator
Staff member
Supporting Member
Moderator
Joined
Apr 5, 2009
Messages
5,197
Location
northeast USA
This is difficult to answer because Shor labels it’s chemicals specifically so you do not know what you are using. One thing strange is you ended up with a brown mud after the first drop. Now if that was a normal aqua regia reaction, you would have digested the mud from the first drop and had a beautiful red acid if the material digested was gold. The fact that it was green is a red flag. As is the fact it did not indicate positive on stannous.

Did you ever test your stannous chloride with a small drop of solution you know contains gold. That is the first thing I do when a stannous test is negative and I expect differently.

I think a few members who have experience with the Shor process should comment here.
 
Joined
Jul 13, 2022
Messages
26
Location
Massachusetts
Three things here:
1) "One thing strange is you ended up with a brown mud after the first drop". Perhaps I wasn't clear.... the first few beakers of Shor AR mixed back in May of 2022 was golden color (after filtering). Then I dropped the gold with the Shor Product and recovered and rinsed the brown precipitant (which I called mud in the above post). I never saw a red liquid. That was back in May of 2022.

2) Fast forward to September 2022 where I am now .... I recovered the brown sediment from the bottom of the "pregnant bucket" weeks after the addition of the copper. This brown sediment is what puzzles me and caused me to start this thread.

3) I did not test the integrity of my stannous on a known gold solution.... However, I have another, newer bottle of stannous that I will try later today.
 

Yggdrasil

Moderator
Staff member
Moderator
Joined
Oct 30, 2015
Messages
2,065
Location
Norway
Three things here:
1) "One thing strange is you ended up with a brown mud after the first drop". Perhaps I wasn't clear.... the first few beakers of Shor AR mixed back in May of 2022 was golden color (after filtering). Then I dropped the gold with the Shor Product and recovered and rinsed the brown precipitant (which I called mud in the above post). I never saw a red liquid. That was back in May of 2022.
Red is with concentrated solution dilute will be yellowish.
2) Fast forward to September 2022 where I am now .... I recovered the brown sediment from the bottom of the "pregnant bucket" weeks after the addition of the copper. This brown sediment is what puzzles me and caused me to start this thread.
Where did the copper come from?
You said nothing if copper?

3) I did not test the integrity of my stannous on a known gold solution.... However, I have another, newer bottle of stannous that I will try later today.

Can you please go in detail what you have done?
 
Joined
Jul 13, 2022
Messages
26
Location
Massachusetts
Hello Yggdrasil,

"Can you please go in detail what you have done?"
Yes, Steps #1 - 10 listed above, are the details to the best of my recollection. Is there something
in particular that I need to further explain?

"Where did the copper come from? You said nothing if copper?"
I added high quality copper tubing to my 5 gallon AR bucket when I saw no precipitant and no gold in solution (#7 above).
When in doubt, cement it out?

Thank you.
 

Yggdrasil

Moderator
Staff member
Moderator
Joined
Oct 30, 2015
Messages
2,065
Location
Norway
It is kind of complicated (and procedurally messy) so I will be terse. I am a beginner and I want to be respectful of your time, so here goes:

1) In several iterations, I placed a couple of pounds of circuit boards and assorted gold plated devices (with significantly visible gold) in a beaker and used the Shor International Product (I know it is frowned upon here) to create AR. All went well and I observed plenty of purple stained stannous tests.
Did you dissolve ALL base metals?
2) I then used urea (I know, that too is frowned upon here) to denox. I still had plenty of purple stained stannous tests. Frequent filtering the solution is implied here.
No comment.
3) Dropped the gold with their product (Shor Quadratic Precipitant). So far, so good....had brown mud at the bottom of the beaker.
All ok, but why use a product that is waay more expensive than the clean product.
4) Cleaned mud with ammonia and then distilled water (as they suggested). Now everything goes south...
I have never used Ammonia or had the need to use it.
5) I attempted to refine this accumulated mud even further using the same procedures above. This left me with approx 3 gallons of green AR with no precipitant and NO gold in solution - all negative stannous tests.
How did you end up with 3 gallons???
How much powder was there?
One tell tale here would be the green color, which means it has Copper in it
, where did the copper come from?

6) I added lots of SMB and no change.
Was this the “quadratic precipitant”?
Did you check that the solution still was acidic? Since it was 3 gallons, was this the full AR or diluted?

7) I then added clean copper pieces to the 5 gallon bucket (hoping to cement out the gold) and after a couple of weeks, I recovered quite a bit of brown precipitant.
Did you have air bubbling or other circulation going in the bucket?
8) I HCL rinsed it (warm) and Distilled rinsed it (warm) until it was clear - and then dried the brown powder.
No comment
9) I used the Shor Product (a nitric acid substitute) one more time with 10 grams of this newly acquired power - then heated it about a hour.
Nitric substitute only?
10) Then this Stannous test went from dark brown to clear in 2 seconds.
Dark to clear may mean false positive or too much oxidizer(Nitric).
11) I know there is gold in there and I do not want to discard it.
You “know” when it tests positive with stannous!
It may be further back in the process.
How much boards did you strip?

Thanking you all in advance....
 

Yggdrasil

Moderator
Staff member
Moderator
Joined
Oct 30, 2015
Messages
2,065
Location
Norway
Hello Yggdrasil,

"Can you please go in detail what you have done?"
Yes, Steps #1 - 10 listed above, are the details to the best of my recollection. Is there something
in particular that I need to further explain?

"Where did the copper come from? You said nothing if copper?"
I added high quality copper tubing to my 5 gallon AR bucket when I saw no precipitant and no gold in solution (#7 above).
When in doubt, cement it out?

Thank you.
I did not see the Copper comment tge first time, sorry for that😏
 
Joined
Jul 13, 2022
Messages
26
Location
Massachusetts
Did you dissolve ALL base metals?
No, there were pieces of copper remaining, probably also nickel, solder, silver and other commercial metals. See photo (items #1 and #5
in the photo). These large pieces and other solids were filtered out before adding the urea.

All ok, but why use a product that is waay more expensive than the clean product.
It came with the starter kit

I have never used Ammonia or had the need to use it.
The woman (with a really nice voice) in their video, suggested it. BTW...it did clean up the mud fairly well.

How did you end up with 3 gallons???
How much powder was there?
One tell tale here would be the green color, which means it has Copper in it
, where did the copper come from?
I mixed many different batches of Shor AR and it just accumulated to ~ 3 gallons. Total powder may have been ~ 20 grams (educated guess). I am weighing everthing now. My gold plated parts have copper base metal.
Was this the “quadratic precipitant”?
Did you check that the solution still was acidic? Since it was 3 gallons, was this the full AR or diluted?
Good question.. I first used their version of SMB (called quadratic precipitant), then I foolishly used a ton of actual SMB in my desperation.
I have sinced learned to settle down.

I just ordered a PH kit, so I do not have that answer yet.

Did you have air bubbling or other circulation going in the bucket?
No air bubbling - just occasional stirring outdoors.

Nitric substitute only?
This morning, I mixed 50 ml of 31% HCL with 50 ml distilled water and added 10 grams of Shor MX3 (their Nitric acid substitute). Their MX3 does not mix well at 31% HCL. I stirred till dissolved then added exactly 10 grams of the brown powder that was at the bottom of this 5 gallon bucket and heated it. Unlike past mixtures, this time it did NOT fume excessively.

Dark to clear may mean false positive or too much oxidizer(Nitric).
I have been guilty of adding too much Nitric in the past (lol)
It may be further back in the process.
How much boards did you strip?

I agree - that is why I added the copper tubes to try to cement it out.
I added maybe a kilo of boards and lots of pieces #5 in the photo (maybe 500 grams of these pieces).

The good news is that this is just a small test that I truely screwed up. I will scale it up once I gain more knowledge.
Thank you.
 

Attachments

  • GOLD.JPG
    GOLD.JPG
    1.4 MB · Views: 0

orvi

Well-known member
Supporting Member
Joined
Apr 13, 2021
Messages
1,070
Location
EU
Oh man :) it will need quite some time to chew this experience :)
No worries, we will fix this.

First off, you need to understand basic chemistry what is going on here... No by brand names (even if the woman in ad has nice voice :D ), but by oxidation states and logic.

Then we can move to actual refining.
First thing is, if using AR, you need to be sure you dissolved ALL metals - because gold is most noble metal from all contained ones - and it will precipitate on any other less noble metal resting in solution.

Second thing is derived from first - due to this fact, pouring some acids on boards is generally a bad idea.
I assume you were after visible gold plating. If you do not see any gold on boards and stuff you fished out of solution, it can be either in liquid or still on the boards - reprecipitated as fine mud.

Forgot the branded unknowns and purchase some HCL and nitric acid. Then we start refining
 

4metals

Moderator
Staff member
Supporting Member
Moderator
Joined
Apr 5, 2009
Messages
5,197
Location
northeast USA
All of this isn't helping AgandAu get to the gold. I thought there was a photo of a beaker full of relatively clean looking precipitate assumed to be gold on this thread. It doesn't help removing photo's that caused us to think one way only to have the story go the other way. EDIT, sorry that photo was on a sodium metabisulfite thread.

Anyway, you used Shor's pseudo regia and it successfully stripped the boards? Down to the resin board or was there still metal on the boards when you pulled them? From what you said, you did a dissolve of the metal on the boards and the solution was what color? If it was aqua regia on copper clad circuit boards it would have been green, dark green.
1) "One thing strange is you ended up with a brown mud after the first drop". Perhaps I wasn't clear.... the first few beakers of Shor AR mixed back in May of 2022 was golden color (after filtering). Then I dropped the gold with the Shor Product and recovered and rinsed the brown precipitant (which I called mud in the above post). I never saw a red liquid. That was back in May of 2022.
The red I referred to was when you re-digested the brown mud, that much gold, would turn the acid red. Because it is substantial gold and few other metals. This is gold that indicated positive in solution from a stannous test. (Question, is the test actually labeled stannous chloride test solution or is it Shor magical mystery juice #1). You precipitated a brown mud after using urea using the Shor precipitating agent (actual chemical name unknown). After the metal dropped you filtered and washed it and soaked it in ammonia. That will get any residual silver chloride and copper out. Did the liquid tint a little blue?

The trouble started when you added this mud to more Shor pseudo regia and it dissolved completely? The solution turned what color? You said green, but after what you started with, presuming it was a once refined gold precipitate which was leached in ammonia, it should not have been green. That is still a giant red flag. At this point, did you test with the Shor indicator before adding more urea and the Shor precipitant?

Let's make sure what I've said here is true before we move on because this is becoming a riot of misinterpretation.
 
Last edited:

Seny2021

Active member
Joined
Mar 27, 2021
Messages
26
It is kind of complicated (and procedurally messy) so I will be terse. I am a beginner and I want to be respectful of your time, so here goes:

1) In several iterations, I placed a couple of pounds of circuit boards and assorted gold plated devices (with significantly visible gold) in a beaker and used the Shor International Product (I know it is frowned upon here) to create AR. All went well and I observed plenty of purple stained stannous tests.
2) I then used urea (I know, that too is frowned upon here) to denox. I still had plenty of purple stained stannous tests. Frequent filtering the solution is implied here.
3) Dropped the gold with their product (Shor Quadratic Precipitant). So far, so good....had brown mud at the bottom of the beaker.
4) Cleaned mud with ammonia and then distilled water (as they suggested). Now everything goes south...
5) I attempted to refine this accumulated mud even further using the same procedures above. This left me with approx 3 gallons of green AR with no precipitant and NO gold in solution - all negative stannous tests.
6) I added lots of SMB and no change.
7) I then added clean copper pieces to the 5 gallon bucket (hoping to cement out the gold) and after a couple of weeks, I recovered quite a bit of brown precipitant.
8) I HCL rinsed it (warm) and Distilled rinsed it (warm) until it was clear - and then dried the brown powder.
9) I used the Shor Product (a nitric acid substitute) one more time with 10 grams of this newly acquired power - then heated it about a hour.
10) Then this Stannous test went from dark brown to clear in 2 seconds.
11) I know there is gold in there and I do not want to discard it.

Thanking you all in advance....
Oh bro thanks for this post as I didn't know how to explain my problem


I burned a couple of ribbons and some cellphone boards too and use hcl and nitric acid but I didn't have enough nitric acid, I probably had about 500ml or less.
After I did that I added some water, and urea. Left it for about 4 hours
Then because I didn't have filter paper I used a cloth and filtered all the hard particles then smb, the next morning got all the muddy stuff under,
The liquid still bluish green tho so I ordered more nitric acid, hcl, urea, smb.
I want to know should I add urea first?
Or should I add more smb?
I didn't have stannous but will have this time so I'm not sure what in there I'm only suspecting there gold because of the کلر

The good thing I didn't use all the boards just a few to see what was going to happen
Thanks
 

Yggdrasil

Moderator
Staff member
Moderator
Joined
Oct 30, 2015
Messages
2,065
Location
Norway
Oh bro thanks for this post as I didn't know how to explain my problem


I burned a couple of ribbons and some cellphone boards too and use hcl and nitric acid but I didn't have enough nitric acid, I probably had about 500ml or less.
After I did that I added some water, and urea. Left it for about 4 hours
Then because I didn't have filter paper I used a cloth and filtered all the hard particles then smb, the next morning got all the muddy stuff under,
The liquid still bluish green tho so I ordered more nitric acid, hcl, urea, smb.
I want to know should I add urea first?
Or should I add more smb?
I didn't have stannous but will have this time so I'm not sure what in there I'm only suspecting there gold because of the کلر

The good thing I didn't use all the boards just a few to see what was going to happen
Thanks
So nobody reads Hokes anymore or search the forum??

The ribbons and the cellphone boards will have less than 1 gram of gold,
likely way less than 0.5g depending on how much boards you processed.

To dissolve that much Gold you need less than 1ml of nitric in HCl.
But since there is a lot of base metals you need way more, but not as much as 500ml.
First of all Urea is for your garden.
Best solution is not to overuse your Nitric, deplete it or use Sulfamic acid.

When going after the Gold directly with AR there is ONE rule, ALL metals needs to be dissolved.
Any base metals left behind will cement out/steal your gold.
Even if it is hidden inside the PCBs it will.

The mud is where the Gold is, at least some of it depending on the previous condition.
The blueish green is to be expected due to the dissolved Copper.
So you should stop here.

Take the mud and boil it in HCl for some time and then water.
What is left behind should be most of the Gold.
Set it aside for later when you have more for a later refining.

What you need to know, is that even though there is golden traces on the boards that is it, there are no Gold inside the boards.
The gold outside the boards may seem like a bit, but it is exceedingly thin so it won't add up to much.
I would guess 0.25g or less per kilo of boards.
 

Yggdrasil

Moderator
Staff member
Moderator
Joined
Oct 30, 2015
Messages
2,065
Location
Norway
No, there were pieces of copper remaining, probably also nickel, solder, silver and other commercial metals. See photo (items #1 and #5
in the photo). These large pieces and other solids were filtered out before adding the urea.
Bad news, much of the Gold has probably cemented out on the remaining base metals. This is the reason we usually diossolve the base metals completely before touching the Gold.

It came with the starter kit
Ok

The woman (with a really nice voice) in their video, suggested it. BTW...it did clean up the mud fairly well.
It will take the AgCl and some Copper depending on the time.

I mixed many different batches of Shor AR and it just accumulated to ~ 3 gallons. Total powder may have been ~ 20 grams (educated guess). I am weighing everthing now. My gold plated parts have copper base metal.
Still How did you end up with 3 gallons from 20g of powder?? Did you pour off the liquid before trying to refine it? I can't quite wrap my head around what you did here.
Good question.. I first used their version of SMB (called quadratic precipitant), then I foolishly used a ton of actual SMB in my desperation.
I have sinced learned to settle down.

I just ordered a PH kit, so I do not have that answer yet.


No air bubbling - just occasional stirring outdoors.


This morning, I mixed 50 ml of 31% HCL with 50 ml distilled water and added 10 grams of Shor MX3 (their Nitric acid substitute). Their MX3 does not mix well at 31% HCL. I stirred till dissolved then added exactly 10 grams of the brown powder that was at the bottom of this 5 gallon bucket and heated it. Unlike past mixtures, this time it did NOT fume excessively.


I have been guilty of adding too much Nitric in the past (lol)


I agree - that is why I added the copper tubes to try to cement it out.
I added maybe a kilo of boards and lots of pieces #5 in the photo (maybe 500 grams of these pieces).
So at best you will have around 0.5 to 1g of Gold, most likely a lot less sinc much is cemented in the boards. In a gallon it will be practically invisible. You relly need to do AP on this kind of material.

The good news is that this is just a small test that I truely screwed up. I will scale it up once I gain more knowledge.
Thank you.
As I asked Seny, have you read C. M. Hokes book or tried searching the forum at all???
 
Joined
Jul 13, 2022
Messages
26
Location
Massachusetts
Hello All,
My sincere thank you for your valued input! I have decided to conclude this thread because:
A) I was a real beginner when I mixed this batch back in May of 2022 (and I had not yet discovered this Forum)
B) I do not have sufficient details/photos/memos/memory of exactly what I did, to provide to you
C) I do not want to waste your time helping me trying to recover the gold in my periodic table of soup. I know there is gold in
there and I will eventually find it - even if I have to FedEx it into the bucket :)

Accordingly, I have regrouped, searched, read and will document all actions going forward. I also ditched the Shor International Products
and ordered Concentrated Nitric Acid. Thanks again gentlemen.
 
Top