Mother Of All Contests Framework

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This is the info I was able to find on http://taxfreegold.co.uk/redspotsongoldcoins.html

Red spot can occur on almost any gold coin, it certainly happens on 22 carat gold coins. We have never seen it on .999(9) fine gold coins, and presume it is virtually impossible for it to occur on fine gold.
From our knowledge of metallurgy, we can tell you that when gold is alloyed, usually with copper or copper and silver, the alloying is obviously done in the molten state, and then has to cool. During cooling, crystalisation occurs, the crystal forming around "seeds" which are molecules of the elemental metals. There is a slight tendency for the elements with the highest melting point to start to crystalise first, and this can lead to small localised areas with slightly higher or lower concentrations of the constituent elements. In ternary alloys (three elements) three pairs of binary (two elements) alloys can also form. These areas of variable alloy are usually of microscopic proportion, but can sometimes be large enough to be visually discernable.
Copper oxidises and forms other salts fairly readily whereas gold is almost completely inert, and silver lies in between, although it is fairly unreactive. This means that if some parts of the alloy are copper rich, and are exposed on the surface of the coin, then it is possible for these parts to exhibit toning or tarnishing. The red spots are areas with a higher copper content, and as copper is a red coloured metal, this shows itself in an area which is less yellow and more red than the rest of the coin. If this area subsequently tarnishes, it would almost certainly go towards a deeper red or brown colour. Whenever we have seen red spot, it has always been an area about the size of a pinhead, sometimes with more than one spot on a coin.

 

They are called copper spots which is sort of a misnomer. Many say that these spots will develop on a coin that is part copper and part gold, and it is because of the copper that these spots will develop but that is not true. Even .999 fine gold can develop these spots over time. This is because .999 fine gold leaves a .001 for the impurities that cause chemical reactions which eventually lead to red spots developing over time. For example the presence of Silver (Ag) and Sulfur (S) even in small amounts on a gold coin can cause these spots over time. The same case is true for gold coins of other levels of purity.
The Intercept Shield won't stop this chemical process because by the time these gold coins have arrived to the Intercept Shield they have already been exposed to elements that cause red spots. And I don't mean just the environmental factors. In many cases many gold coins are already infused with elements that cause red spots. This is of course the .1% out of the 99.9% pure gold coin or any other number of mixtures with gold that leaves the chance for impurities to affect gold coins. At least that is my understanding.

 

Ok.... I'm going to jump right in and put out some theory, based on my near-total non-knowledge of chemistry and metallurgy, etc., but only from reading a few things on the web and trying to make some sense with that and a result that gold coins "red" spot (not other colors) after leaving the mint, that they sometimes will turn blue later, and that if you reverse the red spot professionally (by means of really harsh nasty chemicals you don't want to fool with as an amateur) you not only reverse it but it doesn't come back. Hmmmmm.... To me that means that there is some impurity on or in the coin that is reacting to an environment different from that when it left the mint. And that the something that is reacting was in the minting or the processing/preparation of the alloy or the gold itself.......And that this impurity is not a regular metal that is just mixed in with the alloy to keep the gold from being too soft to hold a shape. (Longwinded, but.......) I am thinking this is something that is could be a remnant from the smelting process for the gold and or from the mint in 'cleaning' up either it's gold planchets, strips, or in the mint for other purposes of cleaning or preparation of dies, etc. Since the problem of red spot gets worse with humidity and intercept doesn't seem to protect (my take on a quick reading of the Lucent technology on this ---- but spent nearly nil amount of time trying to weigh my thoughts and conclusions of this, since I don't have a background sufficient to do so properly ---- so I could totally be wrong) against corrosion of anhydrous particulates, like calcium chloride, that it might be unintended anhydrous particulates that have not been removed sufficiently from the hardening alloy or the smelted gold as it was prepared or something along that line, and that it is actually corrosion of a 'salt' particulate or the like that you are seeing. But it doesn't seem that calcium chloride particulates should be in the mix ever... However, anhydrous Borax is used, apparently in some sort of process, I think..... So ---- long story short, I think it is anhydrous particulates not supposed to be in the alloy but which are not cleaned enough from use to not remain that either embed on the coin's surface or is embedded in the coin alloy. And that it takes the presence of both oxygen and water content in the air (i.e., humidity) to trigger the process of corrosion. I don't think that gold is toning, but it is a foreign particulate that is corroding that you see with 'red spot'. And Intercept is not going to vacuum out oxygen from around a coin nor is it going to dehumidify that oxygen/atmosphere to the point of having the particulates remain anhydrous (without moisture).

Ok.... now either trash this totally and tell me why, or say what could and could not be with my theory.

 

I think what spock said at the beginning of the post says it all. He said, "Simple 2 part question here."
The answer to part 1 is simply that gold tones. If it didn't there would be no possible way that the Gold Bisons, which are .9999 gold, would turn red. Do you realize how small .0001, or 0.01%, of a coin is. It sure wouldn't make up a noticeable spot to the naked eye. It would probably take a pretty strong microscope. The $25 Bison weighs 15.552 grams so that would be only 1.5 one thousandths of a gram. That is not even a grain of sand folks. It is also known that 400-700 years ago, gold coins were made of 100% pure gold. That's 1.0000. There isn't even the slightest trace of copper or gold. Guess what? They sometimes got red spots. Gold reacts/dissolves with aqueous cyanide solutions in the presence of air. Keep a gold coin in a house full of smokers in the humid south, and you have problems. It also reacts with chlorine, bromine, and iodine. So, it's just a fact that sometimes gold tones.
The answer to part 2 is that Intercept Shield was designed to protect copper and silver from corrosive atmospheric sulfur trace gases. Gold simply does not react with sulfur.

I have to say, this was very interesting spock. I learned a lot about gold I didn't know. Keep 'em comin'!

 

1. gold tones...plain and simple
2. ain't nothin' to fix...refer to 1.

 

How does a huge pile of new old stock not clean sweep this lil extravaganza???

 

During cooling, crystalisation occurs, the crystal forming around "seeds" which are molecules of the elemental metals. There is a slight tendency for the elements with the highest melting point to start to crystalise first, and this can lead to small localised areas with slightly higher or lower concentrations of the constituent elements. In ternary alloys (three elements) three pairs of binary (two elements) alloys can also form. These areas of variable alloy are usually of microscopic proportion, but can sometimes be large enough to be visually discernable.
Copper oxidises and forms other salts fairly readily whereas gold is almost completely inert, and silver lies in between, although it is fairly unreactive. This means that if some parts of the alloy are copper rich, and are exposed on the surface of the coin, then it is possible for these parts to exhibit toning or tarnishing. The red spots are areas with a higher copper

Part 2 is because it is not caused by sulfer but by higher copper areas

 

Improper mint wash: some moisture (water with or without added chemicals) gets trapped on the coin and then is prevented from evaporation or otherwise escaping the surface, causing it to bond with and/or etch onto the surface.

This is not dissimilar to the development of a fungal infection: if the skin isn't cleaned off properly before applying a protectant such as desitin or other salves, the ointment itself locks the contaminant in and prevents it from simply rubbing off due to contact with clothes or a diaper. How's that for a metaphorical homology?

 

I will give you the simple answers.

Cause;
Sulfide/sulfate probably on silver.

Intercept shield;
Won't stop the coloration because the ingredients are already present on/in the coin.

 

Yup I was too slow jumping on this one.
the spots themselves are caused by impurities in the gold planchet, bits of iron or copper (possibly even from micro die chips that were imbedded during the minting process) over time these oxidize or corrode causing the spotting. As these are inherent to the coin/planchet itself no storage method short of an oxygen free environment is going to stop them from progressing.
Late with the answer and it has all pretty much been said already, but this was how it was explained to me years ago.

 

This has come up several times, and most are looking at this from the "classical chemistry" mode rather than from the Quantum chemistry mode which does more to explain. Classic chemistry can not tell us why gold, copper , silver can have color as metals. The Bohr atom/electron shell based chemistry can not explain the quantum aspects of the metallic bond (not in classical chemistry). Only the skin of these metals show color according to current papers.

http://en.wikipedia.org/wiki/Metallic_bonding

And below article does explain metal color this level and why the color of gold, silver, and copper can vary in solutions ( alloys) with other metals. The 'Skin' of the metal surface can ( in case of copper and silver) can react with surface contaminants, but the natural color of the metal is created by the quantum action beneath the surface layer.

http://www.webexhibits.org/causesofcolor/9.html

Also other supportive articles for those who do understand quantum effects and color some.

http://www.basqueresearch.com/berria_irakurri.asp?Berri_Kod=4222&hizk=I#.UofQVOI7ze4

http://www.fourmilab.ch/documents/golden_glow/

These explain 'ruby-red' appearance of nanoclustered gold atoms in small loci.

http://www.ncbi.nlm.nih.gov/pubmed/22720781

http://www.nano.gov/nanotech-101/special

There are many others that are written in a deeper math foundation, but these should indicate that a .9999 or better gold mass can exhibit other coloration than 'gold'. but that doesn't mean it is from a contaminant or other material, but possible from underlying metallic bonding or gold nanoparticle localization . Good Reading

 

Come now GD surely you would not have seen a purple colored gold coin before

 

The red spots known as "strawberries or strawberry spots" are present due to the alloying of the coin with copper. The more pure a gold coin is, the less likely it will tarnish.

It was unfortunate to learn of this fact, due to the fact I was always told it was gold from a treasure chest with Pirate blood splattered on it. Way more intriguing than copper tarnish, don't you think?

The reason intercept shield won't stop this from happening is they are not designed to stop copper oxidizing.

 

Question #1 They are called "strawberries" and can range from orange to bright red like blood. They are caused by impurities in the air during minting and react depending on storage, most places that mint gold mint other metals and the dust is in the air and gets stamped onto the surface of the bar or coin where it reacts with sulfur and other contaminates in the air.

The intercept shield boxes can not fix the fact the coins have impurities, basically if the coins are exposed to the right air temp and conditions weather it is in the intercept shield box or not it can still cause the reaction which will result in spots on the coin. Also intercept shield boxes are not airtight more or less allowing the reaction to take place !!

 

Q.What causes red spots on pure gold coins (ex first spouse, buffalo panda etc)? Ill give you a free hint the oil theory is nothing but hogwash.

A.What is the cause of these "red" spots on our precious oh dear precious gold coins? Well first things first gold is never ONE HUNDRED (100) percent pure. It can be .999 .9999 .99999 but it will never be truly 100% pure so other impurities such as copper for example causes it. Gold does NOT corrode because it does not react with oxygen. The "red" spots are areas that have high levels of copper and because copper is a red colored metal, this shows itself in an area which is less yellow and more red than the rest of the coin. If this area subsequently tarnishes, it would almost certainly go towards a deeper red or brown color. Whenever we have seen red spot, it has always been an area about the size of a pinhead, sometimes with more than one spot on a coin.

Q. The second part of the question is why wont intercept shield stop this from happening?

A. Intercept shield is just a coin product, it does not control or fix impurities in any coins.

Some information was taken from taxfreegold.co.uk
Thanks!

 

These spots you speak of on gold coins are not an area of specialty for me. Apparently they are from impurities in the gold reacting to the environment, and are bound to show up even if stored in an intercept shield box. Maybe they can be removed with a Dremel tool set on high.

 

from http://en.wikipedia.org/wiki/Gold(III)_oxide

"Gold(III) oxide (Au2O3) is the most stable oxide of gold. It is a red-brown, thermally unstable solid that decomposes at 160 °C.[2] The hydrated form is weakly acidic and dissolves in concentrated alkali to form salts that are believed to contain the Au(OH)4− ion.[2]

Anhydrous Au2O3 can be prepared by heating amorphous hydrated gold(III) oxide with perchloric acid and an alkali metal perchlorate in a sealed quartz tube at a temperature of around 250 °C and a pressure of around 30 MPa.[3]

Gold oxide is used to make highly-valued red-coloured or cranberry glass, which, like colloidal gold suspensions, contains evenly-sized spherical gold nanoparticles."