Gold electroplating strips pretty well, but, will gold filled or rolled gold plate do OK?

[Nevadayote]

My gold stripping cell works very well with gold plated stuff. However, I was just wondering how well it would work for gold filled or rolled gold plate items. I'm well aware that a chemical process is considered to be better. I'm still curious though and would love to hear from people who have placed gold filled or rolled gold plated things into their stripping cells.

 

[Martijn]

I have heard that it does not work on karat gold or gold filled, but I once dissolved a Karat piece in the cell.

Why not try it in a small clean cell with one small piece? The kind of filler/base material matters a lot, I can imagine.

 

[nickvc]

The one possible problem may be the silver content in the alloy , I’m not sure that will dissolve or if it will passivate the alloy after a while but worth a try.

 

[Deathstar_69]

Gold-filled and rolled gold can be a bit trickier in stripping cells. While gold plating comes off pretty easily, gold-filled typically has a thicker layer of gold, so it might take longer or need more attention. It can still work, but you may need to be more patient.

That said, a chemical process is usually more efficient for these materials. It’s interesting to see how different gold layers react in the cell though! Have you tried adjusting your solution or voltage for better results?

 

[BGDOCK]

I found 8volts and 2 amps works well with gold filled items

 

[Yggdrasil]

Gold-filled and rolled gold can be a bit trickier in stripping cells. While gold plating comes off pretty easily, gold-filled typically has a thicker layer of gold, so it might take longer or need more attention. It can still work, but you may need to be more patient.

That said, a chemical process is usually more efficient for these materials. It’s interesting to see how different gold layers react in the cell though! Have you tried adjusting your solution or voltage for better results?

Not much to adjust with the solution.
It is pure concentrated Sulfuric.
And it has to be concentrated above 90%.

 

[Yggdrasil]

I found 8volts and 2 amps works well with gold filled items

How do it react to the base metals as the GF layer disappear?

 

[BGDOCK]

I pull it out when my wattage drops a little gold is left on , the next step would be to run through a copper cell ( thanks shark )

 

[Quan Jin]

My gold stripping tank works great on gold plated items.However, I was just wondering how well it works on gold plated or tumbled items.I am well aware that the chemical process is considered better.However, I'm still curious and would love to hear from those who have put plated or tumbled gold items into stripping tanks.

Yes, you could try dissolving and then electrodepositing, followed by electrolysis

 

[Yggdrasil]

Yes, you could try dissolving and then electrodepositing, followed by electrolysis

Welcome to us.

 

[Martijn]

The one possible problem may be the silver content in the alloy , I’m not sure that will dissolve or if it will passivate the alloy after a while but worth a try.

I've found different types of karat gold completely dissolve in the sulfuric cell.
as with all thicker pieces, it will take longer. depending on the filler material, you could strip those in the cell.
I will test 18K and 14K @ 1 Amp for 1 hour to see what the dissolution rate is. i don't think Voltage is relevant when you limit the current to 1 Amp.
But so far I guesstimate 0.5 grams per amp per hour.
When laying the pieces in a copper basket or perforated copper cup, they will completely dissolve, when held in clamps, a piece can fall off or become too small to stay clamped. they can be strained out and melted in one bigger piece to put it back in the cell.

 

[Martijn]

I've found different types of karat gold completely dissolve in the sulfuric cell.
as with all thicker pieces, it will take longer. depending on the filler material, you could strip those in the cell.
I will test 18K and 14K @ 1 Amp for 1 hour to see what the dissolution rate is. i don't think Voltage is relevant when you limit the current to 1 Amp.
But so far I guesstimate 0.5 grams per amp per hour.
When laying the pieces in a copper basket or perforated copper cup, they will completely dissolve, when held in clamps, a piece can fall off or become too small to stay clamped. they can be strained out and melted in one bigger piece to put it back in the cell.

Which would leave inquarting karat gold with silver as a thing of the past, for the small hobby refiner with time, not for the big "need to get this 10 ton batch done ASAP" boys'

And that is awesome as the big boys can still buy nitric and the hobbyist can not.

 

[BGDOCK]

I recently tried Poorman’s nitric method to process 300 grams of pins , it took longer and the yield was disappointing. I believe the sulfuric acid stripping cell is the way to go also . I still watch your video on you tube before I crank one up .
Happy new year Martijn.

 

[nickvc]

I've found different types of karat gold completely dissolve in the sulfuric cell.
as with all thicker pieces, it will take longer. depending on the filler material, you could strip those in the cell.
I will test 18K and 14K @ 1 Amp for 1 hour to see what the dissolution rate is. i don't think Voltage is relevant when you limit the current to 1 Amp.
But so far I guesstimate 0.5 grams per amp per hour.
When laying the pieces in a copper basket or perforated copper cup, they will completely dissolve, when held in clamps, a piece can fall off or become too small to stay clamped. they can be strained out and melted in one bigger piece to put it back in the cell.

For higher karat material it may well work but I think that 10k and below you will struggle as I believe the silver content will passivate the material.

 

[Yggdrasil]

For higher karat material it may well work but I think that 10k and below you will struggle as I believe the silver content will passivate the material.

Will Silver passivate in Sulfuric?

 

[nickvc]

Will Silver passivate in Sulfuric?

I really do not know but it isn’t sulphuric when it’s near the anode hence my suggestion to try a sample to find out.
I really don’t like the sulphuric cell as I think concentrated sulphuric is amongst the most dangerous reactants we use.

 

[Yggdrasil]

I really do not know but it isn’t sulphuric when it’s near the anode hence my suggestion to try a sample to find out.
I really don’t like the sulphuric cell as I think concentrated sulphuric is amongst the most dangerous reactants we use.

True

 

[Martijn]

hence my suggestion to try a sample to find out

I will do some pure silver to test and let you all know.

 

[Martijn]

Will Silver passivate in Sulfuric?

I really do not know but it isn’t sulphuric when it’s near the anode hence my suggestion to try a sample to find out.
I really don’t like the sulphuric cell as I think concentrated sulphuric is amongst the most dangerous reactants we use.

it passivates.
I just put some pieces in a small cel and it starts with a current flow (1 A) when there is silver exposed, but it drops fast and a black layer of silver oxide covers the piece which limits the current to 60 mA.
The bar weighed 17.26 gr. before and 17.25 gr after 10 minutes.
For those who want to see, i made a video:


Next test will be testing dissolution rate of 18K and making some 8K gold and see what that does. If that dissolves, there is no need to test anything lower i guess.

White gold should be interesting, as platina does not strip in a cell.
I had combined plating (Au / Pt) on rings, and only the gold was stripped.

 

[nickvc]

Martijn most gold filled / rolled gold alloys used in the UK is around 12% Ag , I’m not sure what they use in the US so make your alloy around the same percentage , higher karat alloys have less silver usually so the silver content should pose no problems very similar to using AR .