2 lbs of gold leaf

[Emryst]

Ok so i got my hands on about 2lbs of 15" x 17" sheets gold leaf. I dont have a count on sheets yet but my math suggests around 98 sheets. I know the gold content of gold leaf is really low its not worth the chems to refine but im thinkin 2 lbs (1lb 11.8oz to be exact) might worth it. Test show it's between 10k and 14k with acid testing. 14k started to react but took like a minute and gold foil was still there so I'm thinking it got to the base metal and 10k didn't react.
I can't get it off the paper cause it's really old leaf.
Research says gold leaf has silver as base metal, but given the thinness of the leaf i dont think it's worth going thru nitric and just go right into AR with it.

So my question is inquart worth it with the thinness of the leaf there maybe loss in values. Also i know ar will disolve filter paper so I'm thinking this tissue paper should be no problem there is so much of it.

I did ruff calculation and a sheet weight is ~8g - paper is ~5.79g and leaf is ~2.2g factor a 10k any higher is a + that's .83 - .91g per sheet. Anyway my math suggest a yield of 83g - 89g. I usually take lower numbers so if yield is higher then I'm figuring the right values if lower I usually try to figure out what or where I went wrong lol in math or refining.
Right now I just trimming the paper edges to cut down on the paper volume

Any thoughts or experiences on best way to proceed with this would be appreciated.

 

[goldshark]

There is Gold leaf (less than 3 microns ), and Gold foil. The difference is in the thickness. The last Gold foil I bought was 24K @ 5 microns. Lately, I haven't seen it in 10/14 K. You might want to either get an XRF shot, or assay 1 piece yourself. Can you see through it, if you hold it up to the Sun? If so, it is refinable with only Nitric. Dealing with Gold foils is an art in itself, requiring special products from a guilding supply house. A simple solution is to combust the paper backing, or pyrolyze. The foil will fly away if you do it in an open air combustion. A fine screen lid would be my first technique. Others feel free to comment.

 

[Emryst]

There is Gold leaf (less than 3 microns ), and Gold foil. The difference is in the thickness. The last Gold foil I bought was 24K @ 5 microns. Lately, I haven't seen it in 10/14 K. You might want to either get an XRF shot, or assay 1 piece yourself. Can you see through it, if you hold it up to the Sun? If so, it is refinable with only Nitric. Dealing with Gold foils is an art in itself, requiring special products from a guilding supply house. A simple solution is to combust the paper backing, or pyrolyze. The foil will fly away if you do it in an open air combustion. A fine screen lid would be my first technique. Others feel free to comment.

Ok well i was told it's gold leaf but I don't think that person knew the difference either. That said it's night now and holding it right next to a light you can't see thru it. I'll check with Sun tomorrow if not raining. I can try to incinerate the same method i do my filters with a large pot and screen on a propane stone and a mapp torch at the top but wont the paper back disolve in solution enough to be filtered out? Throwing this in AR won't do anything in disolving the gold? I'll try taking some to melt in the smelter tomorrow to get a button and get a scratch test on that, just concerned with smelting with all the paper included. This is only some of the sheets it's pretty old so its hard to peel off paper it got stuck on. Guy i got it from said they got it from an old estate sale in L.A. I Google what type of leaf there is
"Gold leaf comes in a variety of karat values and shades which vary from yellow to silvery. 24k gold is 99.9% gold and is yellowish in appearance. 12k is 50% gold and the rest usually silver, which results in it frequently being called White Gold. 22k gold leaf is about 92% gold, and is commonly used for picture frames." That's what it said.

Photo is some of it with the small tray of some that came off easily.

 

[snoman701]

There are two ways I know of. The first is pyrolizing in a closed container, then oxidizing in an electric kiln, then proceeding with aqua regia recovery. I have done this, and it works well. The second is to just boil the whole thing in aqua regia...paper and all. The paper pulps out and you then filter it. I haven't tried this.

 

[goldshark]

Ok well i was told it's gold leaf but I don't think that person knew the difference either. That said it's night now and holding it right next to a light you can't see thru it. I'll check with Sun tomorrow if not raining. I can try to incinerate the same method i do my filters with a large pot and screen on a propane stone and a mapp torch at the top but wont the paper back disolve in solution enough to be filtered out? Throwing this in AR won't do anything in disolving the gold? I'll try taking some to melt in the smelter tomorrow to get a button and get a scratch test on that, just concerned with smelting with all the paper included. This is only some of the sheets it's pretty old so its hard to peel off paper it got stuck on. Guy i got it from said they got it from an old estate sale in L.A. I Google what type of leaf there is
"Gold leaf comes in a variety of karat values and shades which vary from yellow to silvery. 24k gold is 99.9% gold and is yellowish in appearance. 12k is 50% gold and the rest usually silver, which results in it frequently being called White Gold. 22k gold leaf is about 92% gold, and is commonly used for picture frames." That's what it said.

Photo is some of it with the small tray of some that came off easily.

When in doubt, try it on a small scale, before ramping up production. Try putting in 50/50 Nitric distilled water, and some in AR.

 

[nickvc]

If it’s true gold leaf it will be fine gold as that is very ductile which allows it to be rolled and hammered so thin, a simple test is drop a spot of nitric on it if it turns blue / green it’s junk but if nothing happens you have gold.
I have never encountered karat leaf as I believe it wouldn’t hold together in very thin sheet form.

 

[Emryst]

There are two ways I know of. The first is pyrolizing in a closed container, then oxidizing in an electric kiln, then proceeding with aqua regia recovery. I have done this, and it works well. The second is to just boil the whole thing in aqua regia...paper and all. The paper pulps out and you then filter it. I haven't tried this.

I'm thinking the AR boil is my way to go. But I have not done any mixed metal AR before since using this method nitric dissolution is not done. Do i percipitate base metal out first cause I think its silver? I dont want to have the base dropping with the gold.

 

[Emryst]

When in doubt, try it on a small scale, before ramping up production. Try putting in 50/50 Nitric distilled water, and some in AR.

I'm working with only half the sheets right now. My concern with splitting the sheets into smaller batches then this the yield will be so small I won't notice it drop. So i want to tap the brain trust here to go with the most advantage method i have means to do with my limited refining setup. That way I know better with the rest.

 

[Yggdrasil]

I'm thinking the AR boil is my way to go. But I have not done any mixed metal AR before since using this method nitric dissolution is not done. Do i percipitate base metal out first cause I think its silver? I dont want to have the base dropping with the gold.

According to Nickvc there should be no base metal if it is true Gold leaf as karat will probably not be possible to get this thin.
Check a spot with Nitric.

 

[Emryst]

If it’s true gold leaf it will be fine gold as that is very ductile which allows it to be rolled and hammered so thin, a simple test is drop a spot of nitric on it if it turns blue / green it’s junk but if nothing happens you have gold.
I have never encountered karat leaf as I believe it wouldn’t hold together in very thin sheet form.

Isn't using nitric the same as an acid test used for scratch testing? But with straight 70% nitric that equivalent to a 24k gold test right?

 

[Emryst]

If it’s true gold leaf it will be fine gold as that is very ductile which allows it to be rolled and hammered so thin, a simple test is drop a spot of nitric on it if it turns blue / green it’s junk but if nothing happens you have gold.
I have never encountered karat leaf as I believe it wouldn’t hold together in very thin sheet form.

Isn't using nitric the same as an acid test used for scratch testing? But with straight 70% nitric that equivalent to a 24k gold test right?

 

[Emryst]

According to Nickvc there should be no base metal if it is true Gold leaf as karat will probably not be possible to get this thin.
Check a spot with Nitric.

Yeah I read that.

 

[Emryst]

If it’s true gold leaf it will be fine gold as that is very ductile which allows it to be rolled and hammered so thin, a simple test is drop a spot of nitric on it if it turns blue / green it’s junk but if nothing happens you have gold.
I have never encountered karat leaf as I believe it wouldn’t hold together in very thin sheet form.

It does come in lower karat but sadly mine does not look like these and it is probably junk leaf. Nitric turn lighter color of blue not really green tho.

 

[goldshark]

There are a few imitation leaf foils out there, not really sure what they are composed of. Some are plastic. Hit it with a Bic lighter and see if it is completely consumed, or if some metal is left. A 1" x4" strip will tell the tale. Hold with tweezers, forceps, tongs or quick fingers, if you don't have any of the others. Hold it above the lighter.

 

[Emryst]

There are a few imitation leaf foils out there, not really sure what they are composed of. Some are plastic. Hit it with a Bic lighter and see if it is completely consumed, or if some metal is left. A 1" x4" strip will tell the tale. Hold with tweezers, forceps, tongs or quick fingers, if you don't have any of the others. Hold it above the lighter.

Just did that its some type of metal it didn't melt or warp to the heat of a lighter. Turned color tho like a rainbow effect

 

[Emryst]

There are a few imitation leaf foils out there, not really sure what they are composed of. Some are plastic. Hit it with a Bic lighter and see if it is completely consumed, or if some metal is left. A 1" x4" strip will tell the tale. Hold with tweezers, forceps, tongs or quick fingers, if you don't have any of the others. Hold it above the lighter.

Photo of the piece i put lighter too.

 

[goldshark]

Photo of the piece i put lighter too.

Might be anodized Al? Al won't react much with Nitric, but does with HCl.

 

[goldshark]

Photo of the piece i put lighter too.

Just wondering if the paper ignited and completely burned away.