If you guys ever figure out what causes it, great, I'm here to listen. Meanwhile, I'm satisfied to know that gold tones. It works for me
Not only that...but that tiny "dot" is spread equally throughout the coin. There simply isn't enough copper material present to discolor the coin (even if it was all contained in a "dot"). Gold is not completely inert and can tone.
A Better Resolution! Well Stated!! I find your conclusion more satisfying, and less stressful. In lieu of current international environment/problems/dilemmas, I'll accept your peaceful observation, especially since it appears we'll not determine a better resolution in the near future. Thanks for the moderation! :high5:
I do realize what 1/10,000 of a part is. I have a background in analytical chemistry, including quantitative analysis, so I have a decent grasp of the concept. I never said anything about an anomaly covering 50% of the coin. I was only referring to the extremely tiny red specks that I have seen on occasion on modern gold pieces. I have no reason to believe that the tiny specks caused by copper impurities would "grow" to cover any significant portion of the coin's surface.
I realize that, but I was. Look at post #9 in this thread. Easily 50% of the coin is red. And th eone I posted in #7 - 30% of that is red. That's my point, a tiny, tiny amount of any impurity in the metal cannot cause that.
Yeah, I have. But most jewelry is 18k gold at best so it is to be expected. It's not noticed much on jewelry that is worn often though because any toning gets rubbed off by the wearing. The coins we are discussing are 23.9-24k gold.
I went to the safety deposit box yesterday and I happened to take a glance at my 2006 Proof Gold Buffalo. Sure enough, there are 2 red spots on the obverse.
Maybe getting off topic a bit, but this is a relatively high mintage coin meant for bullion buyers. I don't think the PCGS slab and marked with their mostly irrelevant "first strike" designation will make a lot of difference. Given the mintages of this coin and the fact that it is a MS69 I would not expect to get much more than spot for it. Of course the good news is that spot is a lot more now than it was in 2006. ------------- It sounds as if the most common reason for these spots are due to some sort of metal contamination of the die or of the blank before the coin is struck. i.e. it comes down to quality control. I don't have any '06 coins, but I do have a couple of '09 bullion and a proof '09 buff and there are no spots. If it is a quality control issue then I would guess the spots would be limited to certain populations of the coins. It's too bad these spots are not considered in the same terms as some sort of mint mistake or like toning on silver coins. If so, the coins could be a lot more valuable.
gold spots Some things are just what they are, they defy explanation. Until one that makes logical sense is found. Then some will still not accept what appears to be true. It is very difficult to go through life needing an explanation for every thing. You waste a lot of time wondering " What is What ". Pep
Not sure if this is related, but seemed like it could be a factor Polishing A very fine powder of ferric oxide is known as jeweler's rouge, red rouge, or simply rouge. It is used to put the final polish on metallic jewelry and lenses, and historically as a cosmetic. Rouge cuts more slowly than some modern polishes, such as cerium(IV) oxide, but is still used in optics fabrication and by jewelers for the superior finish it can produce. When polishing gold, the rouge slightly stains the gold, which contributes to the appearance of the finished piece. Rouge is sold as a powder, paste, laced on polishing cloths, or solid bar (with a wax or grease binder). Other polishing compounds are also often called "rouge", even when they do not contain iron oxide. Jewelers remove the residual rouge on jewelry by use of ultrasonic cleaning.
Nothing Anything that alters the surface of a coin, can be detected. The flats of a coin can not be done even with a light vapor blast and remain undetectable.If I knew of something I could make a fortune repairing coin surfaces. Will it ever happen, maybe, but not soon. A re strike on the coin with the original die set as they do with proofs might be viable. Where would you get the dies ? They are destroyed ,and you are not legally able to own such items to make American coins. Take care Pep
Jeweler's rouge virtually destroys coins leaving them with a look that is unmistakeable. Even a novice collector will notice it.
No, but the idea is interesting. Basically, you are saying something on the surface of the gold has discolored it. That might have some merit to it. There was opinion that it was oil from the die press. I'm still a believer that even gold oxides to some extent.
I tend to agree, it seems when gold is beaten thin enough the light that will come through is blue-green as gold will react with the yellow and red light.
Perhaps this article will help. Yes, gold can form oxides, but under conditions that are unobtainable outside of a high level laboratory. Under normal conditions where life can exist on the earth, gold would not oxidize. In depths of volcanic magma, under extreme pressure and temperature, bets are off. http://matsci.uah.edu/courseware/mts501/reports/sschwitalla.html Jim
The " Red Spots " that appear on Gold Bars , or coins is simply an anomaly that occurs as a result of a combination of many different factors . To positively say that there is any one cause , is unfounded .
Call it whatever you want Jim, toning, forming oxides, or anything else. But the fact remains, the stuff (gold) changes color. And it does so under normal "life on earth" conditions.