# Testing Gold Powder



## peaksilver2012 (May 5, 2009)

quajtaka asked about testing gold powder and got 2 replies, but he never replied to confirm what his question really was. I will make the same query, and hopefully better define what I'm looking for.

I bought some gold? powder/flake off ebay to practice melting/refining etc. The problem is, I don't know if it really is gold. Harold suggested I use nitric to test it before trying to melt it. Can someone explain to a total noob the process I would use to test it, then the best way to get it to a viable state to melt into a button?

Thank you in advance.

Preston


----------



## goldsilverpro (May 5, 2009)

Anything that dissolves in nitric acid is NOT gold. If you bought "gold flake" off Ebay, the odds are about 1000 to 1 that it is not gold.


----------



## lazersteve (May 5, 2009)

Preston,

If your sole purpose is to test the foils to confirm they are indeed gold just watch my video on using HCl-Cl (the one perfromed in the test tubes) and you can safely and easily determine if a small sample contains gold.

Steve


----------



## peaksilver2012 (May 5, 2009)

Steve,

Watched most of your vids so far. Will check that one out. Thanks zillions.

Preston


----------



## RESET (Sep 6, 2012)

Thread resurrection. A friend of mine inherited a small bag of what she thinks is gold powder. She says that it is like fine sand, slightly heavy and brown. She is bringing it to me tomorrow so i can verify that it is gold. How much of the powder should I put in nitric to test? Will 50% nitric work?


----------



## NobleMetalWorks (Sep 6, 2012)

RESET,

50% is better than 69-70%. If it's diluted some it works better.

All you have to do is put a tiny quantity, just enough that you can see it, on something acid resistant that will not spill the acid when you put it on. Then just a drop, no more, will either dissolve or not whatever sand/powder you are testing.

Scott


----------



## RESET (Sep 6, 2012)

Thanks Scott. Now I have to figure out how to verify that it is gold if nitric doesn't dissolve it. I will be at work and not have access to HCl. Obviously Nitric isn't going to dissolve sand. I will be able to weigh it but don't know how I would get the volume for a mass calculation.


----------



## jimdoc (Sep 6, 2012)

RESET said:


> Thanks Scott. Now I have to figure out how to verify that it is gold if nitric doesn't dissolve it. I will be at work and not have access to HCl. Obviously Nitric isn't going to dissolve sand. I will be able to weigh it but don't know how I would get the volume for a mass calculation.



If it looks like the pure gold powder that you have seen many pictures of here on the forum, then it may not hurt to try to melt a small sample. That would be proof positive also.

Jim


----------



## RESET (Sep 6, 2012)

I have only seen pictures. I don't process gold myself so i have never had it in hand or seen it in person. I don't think melting at work is an option even though I could probably get my hands on a torch.


----------



## NobleMetalWorks (Sep 6, 2012)

If it's brown in color like the pictures that have been posted on this forum of Au "sand", and it does not react with Nitric Acid, then it's almost certainly gold. You will be able to tell right away by weight, look, etc if it is sand or not, if it's more than a gram, just by putting it on a piece of paper and holding it in your hand.

The only metals that don't dissolve in Nitric Acid alone are Gold and PGMs (Platinum Group Metals), Zinc and Aluminum are not the same color as Gold, however if they are present in the powder, they will probably build up an oxidation layer that will protect the metal from being attacked by the Nitric Acid. But honestly, if it is brown like you are describing, you will be able to tell easily enough if it's sand or metal, and with Nitric Acid, if they are base metals or not.

When you do find out, post here, I am interested to see what you come up with. And remember, just a drop, if it is base metals it might even surprise you if it goes "poof"

Scott


----------



## RESET (Sep 7, 2012)

Thanks Scott, I will let everyone know. She is asking me to try to find a buyer but I told her that I would have to make sure it is gold first.

EDIT: Bummer. Her "Gold powder" was just beach sand.


----------



## NobleMetalWorks (Sep 7, 2012)

The real value in this then is that you have learned, so this has actually benefited you at least in that regard.

Scott


----------

