Unidentified compound

[Watcher]

Evening all, happy new year hope you are all well.

Need some help/advice please.

I've successfully done AP on numerous occasions and even done AR successfully...

This has me stumped?

I found this green coloured powder on the bottom of my filter after the second filtration.

It would be great if anyone has or knows what may of happened? TIA.

 

[4metals]

Two quick questions

If you put a drop of stannous chloride on the small piece of paper which I assume was the filter paper the powder came from, is there an indication of gold?

Was the filtration very slow?

 

[Watcher]

Two quick questions

If you put a drop of stannous chloride on the small piece of paper which I assume was the filter paper the powder came from, is there an indication of gold?

Was the filtration very slow?

Filtration the first time was slower than usual, the second was slow and I used alot of sprayed water to clear most of the sludge which incidentally was barren of gold particles...
I have no stanous available at the moment are you thinking it may be precipitated gold?
Oh I should add it was rolled gold from vintage watches.

 

[4metals]

It is not uncommon for the paper to take on a green hue when it is incompletely rinsed and that can often contain values. Easy to test but stannous is needed.

My thought about slow filtration was that if you don't filter and flush the solids on the paper they can become discolored by the acid, not unlike the paper. Based on the texture that may make those unknown solids Silver Chloride which were discolored. You can see if a small bit of it dissolves into ammonia, if it does there is a good chance it is Silver Chloride.

 

[Watcher]

It is not uncommon for the paper to take on a green hue when it is incompletely rinsed and that can often contain values. Easy to test but stannous is needed.

My thought about slow filtration was that if you don't filter and flush the solids on the paper they can become discolored by the acid, not unlike the paper. Based on the texture that may make those unknown solids Silver Chloride which were discolored. You can see if a small bit of it dissolves into ammonia, if it does there is a good chance it is Silver Chloride.

Upon reflection I may of processed some rolled gold which was on a silver pocket watch chain.
I had a hard time trying to find what metals it was so it maybe the culprit.
I still have the AP solution but temperatures have dropped and I'm probably done till spring
I will definetly do an additional AP with the scrap gold I recovered and try and get all the silver out prior to AR.

 

[Yggdrasil]

Upon reflection I may of processed some rolled gold which was on a silver pocket watch chain.
I had a hard time trying to find what metals it was so it maybe the culprit.
I still have the AP solution but temperatures have dropped and I'm probably done till spring
I will definetly do an additional AP with the scrap gold I recovered and try and get all the silver out prior to AR.

Strange as AP should not do much with Silver.
Have you used Nitric at all on this batch?

 

[Watcher]

Strange as AP should not do much with Silver.
Have you used Nitric at all on this batch?

Hi, no, no nitric used I'm wondering if some of my rolled gold may of been karat gold?

 

[Yggdrasil]

Hi, no, no nitric used I'm wondering if some of my rolled gold may of been karat gold?

First make some Stannous and test it.
Could there have been some kind of non metallic filler in the Gold?

 

[Watcher]

Maybe, this piece is the culprit I believe? Jewellers said it wasn't solid but gold filled filled, gold merchant wouldn't but it off me as they bel

 

[Watcher]

Maybe, this piece is the culprit I believe? Jewellers said it wasn't solid but gold filled filled, gold merchant wouldn't but it off me as they bel

Believed it was low karat, my acid tests couldn't confirm it was 10k it was a heavy chain and non magnetic..

 

[Thomas M Joseph]

Looks like nickel compounds from a nickel watch case.

 

[eaglekeeper]

Oh I should add it was rolled gold from vintage watches.

Maybe a little polishing compound mixed with some other stuff... hard to say.

 

[Watcher]

Just took a picture of my filtered AP see the whiteish sludge at the bottom, any ideas?
Thanks.

 

[FrugalRefiner]

Usually, whitish sludge at the bottom of AP is CuCl.

Dave

 

[Watcher]

Yes I believe so too.
I still don't know what the crumbly greenish compound is though not sure what to do with it?

 

[Yggdrasil]

Yes I believe so too.
I still don't know what the crumbly greenish compound is though not sure what to do with it?

Add a bit of HCl and some air to it.
It will transform your CuCl to CuCl₂ and turn the solution green again.