How do you deal with gold lapel pins with metal stick posts?

[didit]

The attached photo is from the internet and is for reference only but my question pertains to similar items.

I have a number of gold service pins that I will include in a refine at some point.

While some have gold posts many have a steel magnetic post. Sometimes the steel posts are actual gold, sometimes they are gold plated, and sometimes just bare steel.

My question is how do process these to remove the steel prior to refining?


Do you just snip off what you can?

Do you melt in a dish and pick out post if it hasn't melted?

Do you just leave the metal post and process it differently?

I know that ferrous items should be separated but am not sure how to go about it with these. Advice?

 

[nickvc]

I’d snip off most of the post and then cover in HCl and heat that should dissolve any steel left.

 

[Alondro]

I’d snip off most of the post and then cover in HCl and heat that should dissolve any steel left.

Not concentrated HCl. If the post is stainless, it won't dissolve in concentrated HCl.

5M HCl would work.

 

[nickvc]

Not concentrated HCl. If the post is stainless, it won't dissolve in concentrated HCl.

5M HCl would work.

I can say if the HCl is hot it will dissolve , most HCl is not too concentrated to allow steel or iron or nickel to dissolve.

 

[anarxi]

mixture of water, nitric acid, and sulfuric acid.
in proportions 1/2/1.
distilled water.
nitric 65%
sulfuric 40%.

 

[Darkthirty]

mixture of water, nitric acid, and sulfuric acid.
in proportions 1/2/1.
distilled water.
nitric 65%
sulfuric 40%.

Nitric is an oxidizing acid and stored in stainless, it has no effect on chromium oxide. HCL, as a reducing acid will attack stainless steel.
Edit to add clarification.

 

[anarxi]

Nitric is an oxidizing acid and stored in stainless, it has no effect on chromium oxide. HCL, as a reducing acid will attack stainless steel.
Edit to add clarification.

I don’t know what the theory says, but in practice the legs of microcircuits (an alloy with a nickel content of about 29%) and transistor housings dissolve perfectly, leaving only a layer of gold plating.

 

[Darkthirty]

I don’t know what the theory says, but in practice the legs of microcircuits (an alloy with a nickel content of about 29%) and transistor housings dissolve perfectly, leaving only a layer of gold plating.

Nitric will attack nickel, the chromium oxide protects the SS

 

[Proffshuggarn]

5M HCl would work.

I accidentally bought 25 liters of 10% hydrochloric acid a year ago because I didn't read the container properly.. This diluted hydrochloric acid might be suitable for my lapel pins?
/Dennis

 

[Yggdrasil]

I accidentally bought 25 liters of 10% hydrochloric acid a year ago because I didn't read the container properly.. This diluted hydrochloric acid might be suitable for my lapel pins?
/Dennis

Should think so.
If you are in no hurry at least.

 

[Proffshuggarn]

Should think so.
If you are in no hurry at least.

Patience is my middle name

 

[nickvc]

I accidentally bought 25 liters of 10% hydrochloric acid a year ago because I didn't read the container properly.. This diluted hydrochloric acid might be suitable for my lapel pins?
/Dennis

Especially if you heat it to a near boil .