Red Spots On Gold Buffalo Surfaces - Bullion Buffalo in PVC - Is there a danger of PVC attacks on Bu

MsMorrisine

Direct from the Mint AP for gold:
The American Buffalo Gold Bullion Coins are individually packaged in a PVC protective covering.


And we know Gold Buffalos develop red spots on the surface.


Could the PVC attack the small areas on the admittedly 99.99% pure gold and turn those areas (instead of red spots) into PVC Green Slime over Time????

fc

You will get differing opinions and speculation. I will refer you to an article by
Doug Winter as he seems to have sway over a lot of people here.

http://www.raregoldcoins.com/market-blog/bass-collection-dirty-little-secret

But in the end even that article uses phrases like:

I don’t know this for a fact
I am not a chemist
I’m not certain

etc... So.. you decide.

ricko

The greatest danger with pure gold in PVC is chemical re-deposition due to deterioration. On 22K coins, certainly it could attack copper flecks in the alloy resulting in a corrosive growth. A cleaning would likely leave an unsightly pit. Gold itself has no reaction with PVC. Cheers, RickO

CEOcoinshopcom

I have heard from our local silver/gold refiner (Sunshine Minting) They have told us that the red spots on gold coins, can be caused by platinum and palladium in the mix.
Don't know, but could be....

mrpotatoheadd

<< <i>I have heard from our local silver/gold refiner (Sunshine Minting) They have told us that the red spots on gold coins, can be caused by platinum and palladium in the mix.
Don't know, but could be.... >>

In some cases, maybe. But not all, I'd think. Some red spots are way too big to be an impurity in a .999 fine coin.

MsMorrisine

and buffs are 99.99% pure

plus bright red is an odd color for oxidized copper.

mrpotatoheadd

My theory is that is machine oil or some other sort of contamination of the planchet during striking. Not that I'm familiar enough with the manufacturing process to say with any certainty, but everybody gets to have an opinion, right?

MikeInFL

The red plague. Argh.

First milk spots on ASEs, now this.

Sad indeed.

CEOcoinshopcom

I thought the red would be for the copper also.
But they said, no that it was for sure platinum/palladium
I also asked... if your gold (sunshine minting) is .9999, then how could you have that much contamination?
They told me that most contaminates migrate to the top, or outside... so any little bit would show up on the surface of the strip the rolled out.
So most of the issue jumps right out to the face of the coin.

Just passing on what they told/taught me. They produce a LOT of Gold and Silver blanks for US mint and Canada Maples.

JazzmanJAB

CEOcoinshopcom

Yep, those are just the spots that they have problems with on their gold.

p.s. I have a theory about the milkspots on ASE's.....
should I open that box?

nibanny

<< <i>Yep, those are just the spots that they have problems with on their gold.

p.s. I have a theory about the milkspots on ASE's.....
should I open that box? >>



Please do!

CEOcoinshopcom

Well, Sunshine Minting, says.... they have a huge problem, a problem that all the refiners have. It's a problem that NONE of them want to talk about (or admit)
Here is the Bad-word of the day..... BISMUTH
All the refiners fight it all the time. Bismuth "likes" silver.... a lot.
So the refiners are always fighting to not get it into their system. It can come in with any silver that they refine... But up here in the Silver Valley of Idaho, there isn't much bismuth in the galena (silver ore) that comes out of the ground here. But since Sunshine Minting has been making the blanks for the USMint SAE blanks, they have had to import LOTS of silver.
Pan American mining has many silver mines, most in South America and those mines are notorius for having bismuth contaminates.

So Sunshine and other refiners are working very hard to get the bismuth out. And one of the tell tale marks that your silver has bismuth, is milk spots on the surface of your finished silver.

Hope this doesn't start WWIII

mariner67

Does this mean dipping in acetone will or will not help prevent white spots on ASEs?
Thanks.

MsMorrisine

<< <i>Well, Sunshine Minting, says.... they have a huge problem, a problem that all the refiners have. It's a problem that NONE of them want to talk about (or admit)
Here is the Bad-word of the day..... BISMUTH
All the refiners fight it all the time. Bismuth "likes" silver.... a lot.
So the refiners are always fighting to not get it into their system. It can come in with any silver that they refine... But up here in the Silver Valley of Idaho, there isn't much bismuth in the galena (silver ore) that comes out of the ground here. But since Sunshine Minting has been making the blanks for the USMint SAE blanks, they have had to import LOTS of silver.
Pan American mining has many silver mines, most in South America and those mines are notorius for having bismuth contaminates.

So Sunshine and other refiners are working very hard to get the bismuth out. And one of the tell tale marks that your silver has bismuth, is milk spots on the surface of your finished silver.

Hope this doesn't start WWIII >>




our chemist here has said that testing of milk spots showed signs of chlorine.

I'd be interested to know if that testing would or wouldn't find Bismuth, too.

ricko

CEOcoinshopcom, galena is lead ore..... interesting input on bismuth though, although I have not seen that specified in any analysis posted so far... Cheers, RickO

TheBigB

<< <i>

<< <i>I have heard from our local silver/gold refiner (Sunshine Minting) They have told us that the red spots on gold coins, can be caused by platinum and palladium in the mix.
Don't know, but could be.... >>

In some cases, maybe. But not all, I'd think. Some red spots are way too big to be an impurity in a .999 fine coin. >>



I have seen data that suggests the problem is not in the mix, but surface contamination from tooling used for other metals like silver.

CEOcoinshopcom

"galena is lead ore"

You're right, most of our silver comes in the galena mix... common language around here, but you're right.

About the Chlorine... chlorine gas is what most refiners use to "bubble through" the liquid metal. It grabs different metals and forms a **** chloride.
Like zinc chloride, copper chloride etc.... when the bismuth forms its chloride, it has an ionic reaction with the silver and wants to "hold on" to the silver....
So the Chlorine bubble doesn't work so well with the bismuth.
They have asked me and others, if you have any ideas, they are very happy to hear them.