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PCGS and NGC MS70 10$ Platinum Eagle 2002
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<p>[QUOTE="Midas, post: 130200, member: 2761"]Platinum is a noble metal. Like gold and palladium, it is resistant to corrosion and/or oxidation. These metals were called "noble" because it was believed that the only people that could afford these metals were people of nobility. </p><p> </p><p>With that said, the only time you will see noble metals corrode and/or tarnish is when they are alloyed with large amounts of other "active" metals. For instance, in Europe, they tend to add more copper (as high as 35%) to their 14kt jewlery mix (which is 58.333% pure gold). This type of jewlery looks more "rosey" than 14kt gold alloys with only 20% copper. If you in an area with a lot of sulfur in the ground water (like central Florida), you will see this type of jewelry discolor frequently. Even worse are people that have these type of gold/cooper crowns in their mouth. Drink some of this sulfide waters and/or high concentrations of ice tea (tanic acid) and your gold crown will in fact discolor.</p><p> </p><p>So, I bring this up because if you alloy a noble metal with an "active" metal, all bets are off...but I seriously doubt that "noble" metals in their <u>pure</u> 99.99% form will ever corrode and/or tarnish. It is one of the reasons why they are great for hypoallergenic cases which basically means, they react with nothing else![/QUOTE]</p><p><br /></p>
[QUOTE="Midas, post: 130200, member: 2761"]Platinum is a noble metal. Like gold and palladium, it is resistant to corrosion and/or oxidation. These metals were called "noble" because it was believed that the only people that could afford these metals were people of nobility. With that said, the only time you will see noble metals corrode and/or tarnish is when they are alloyed with large amounts of other "active" metals. For instance, in Europe, they tend to add more copper (as high as 35%) to their 14kt jewlery mix (which is 58.333% pure gold). This type of jewlery looks more "rosey" than 14kt gold alloys with only 20% copper. If you in an area with a lot of sulfur in the ground water (like central Florida), you will see this type of jewelry discolor frequently. Even worse are people that have these type of gold/cooper crowns in their mouth. Drink some of this sulfide waters and/or high concentrations of ice tea (tanic acid) and your gold crown will in fact discolor. So, I bring this up because if you alloy a noble metal with an "active" metal, all bets are off...but I seriously doubt that "noble" metals in their [U]pure[/U] 99.99% form will ever corrode and/or tarnish. It is one of the reasons why they are great for hypoallergenic cases which basically means, they react with nothing else![/QUOTE]
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PCGS and NGC MS70 10$ Platinum Eagle 2002
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