Non-Chemical Polishing Finished Bars/coins/etc Gold

[jack_burton]

Ran through about 12 pages of search results and didn't see exactly what I was looking for. Mostly posts about polishing waste from jewelers.

My question is, other than "fire polishing" what other methods do you all use to polish your bars and/or coins, whatever you are selling? I've found I generally since what I'm putting out is .999 its got a fairly good shine already. Just wondering what I could do to improve. Ideas?

 

[Smack]

You shouldn't have to polish gold or silver if you do your melt and pour properly. Keep o2 off it and you should do fine. Not too hot and not too cold.

 

[Geo]

nothing. never shine or polish a coin. bars that are pure have a luster that is only blemished if you try to polish making tiny finite scratches, besides pure gold needs no polishing.

 

[Lino1406]

1. A revolving brush + paste
2. Forgive for the word "cyanide" + H2O2
booming (for the experts)

The correct term is bombing.

Harold

 

[dtectr]

1. A revolving brush + paste
2. Forgive for the word "cyanide" + H2O2
booming (for the experts)

My friend
The english word you are looking for is bombing, a very dangerous process involving the use of boiling cyanide and concentrated H2O2. A surface layer of alloyed karat gold only molecules thick is stripped off then only 24k is redeposited - the rest of the alloy remains in the solution.
This process was once used extensively in the jewelry industry where appearance is often more important than purity- I believe this process has no place in refining, that its use would be deceptive at the least, fraudulent at worst.
Unless I am gravely mistaken, gold only as pure as 2N should need no further work, with the exception of time in hot H2O2 to remove flux residue. If the ingots look cheesy they probably are.
I am admittedly no expert, these are just observations from my experiences.

 

[butcher]

impure gold needs refined, polishing the outside will not change that fact the impuritys of other metal are distributed evenly all through the gold, polishing will not raise the karat or value of the gold, it will make jewelry pretty.

ugly gold can have the same value as pretty looking gold.
A smart buyer will not go by looks.

 

[slickdogg]

jack_burton

if you want to get an unbelievable, amazing shine from any type of precious metal
along with the removal of scratches.... there is a polishing/rubbing compound called "mothers" .

It is unreal,
i use it on restoration, and showroom products 8)

 

[publius]

one could try electropolishing... http://www.ep-systems.com/

 

[dtectr]

one could try electropolishing... http://www.ep-systems.com/

... Or learn to practice good technique making polishing unnecessary ... ?-b

 

[publius]

one could try electropolishing... http://www.ep-systems.com/

... Or learn to practice good technique making polishing unnecessary ... ?-b

Smart Butt... :lol: :lol: :lol:

 

[qst42know]

Are you polishing to hide impurities or to create a look?

 

[jack_burton]

What I am pouring now doesn't really "need" to be polished, it's coming out very brilliant when I don't screw up the pour. However, I saw that video posted awhile back about making of the huge Canadian gold coin and it sparked the question.

 

[Geo]

What I am pouring now doesn't really "need" to be polished, it's coming out very brilliant when I don't screw up the pour. However, I saw that video posted awhile back about making of the huge Canadian gold coin and it sparked the question.

i believe the reason they had to polish that was because it had to be milled to spec.

 

[qst42know]

What I am pouring now doesn't really "need" to be polished, it's coming out very brilliant when I don't screw up the pour. However, I saw that video posted awhile back about making of the huge Canadian gold coin and it sparked the question.

That was definitely for the look. Cool coin. :mrgreen: The polished surfaces standing out against the matte background. I don't think that's the look you want on poured bars though.

 

[Harold_V]

What I am pouring now doesn't really "need" to be polished, it's coming out very brilliant when I don't screw up the pour. However, I saw that video posted awhile back about making of the huge Canadian gold coin and it sparked the question.

The coin you spoke of isn't polished. The die is (for the shiny part).
No one in their right mind does anything to a coin or ingot that could be even remotely construed as having altered its content. You can't polish without removing metal. That's never a good idea for a coin or ingot.

Ingots should NOT be adjusted for size. They should be marked according to their actual weight. Any sign of adjustment may also be a sign of the ingot having been shaved. Credibility is lost.

Harold

Edit

I stand corrected. I was wrong about this particular coin.
My sincere thanks to qst42know for providing me with the following statement:

The 1 million dollar coin he is referring to is polished. Made from an investment cast it took a bunch of hand work to get it to look like a struck coin.