Spotting

[burts-migration]

Is spotting on copper coins completely unacceptable, and are the relevant coins worth being submitted for grading.

 

The coins without the spot/spots are ms68.

[BillJones]

Is spotting on copper coins completely unacceptable, and are the relevant coins worth being submitted for grading.

 

The coins without the spot/spots are ms68.

 

It depends upon the nature of the spotting, the overall eye appeal of the coin and the grade of the coin. The lower the grade, the more other shortcomings are not as important. It's hard to go further without specific examples.

 

As for an MS-68, there is no way that a copper coin can grade MS-68 and have an obvious spot.

 

[mkman123]

Its an eye sore in my opinion and I wouldn't like it

[johnny9434]

i pass on coins with spots. to me its not worth the trouble. jmo and welcome to the forums.

[Houston Investor]

I find it can be difficult to find copper coins without some sort of spotting. For me it depends on how severe the spot is. Copper coins are more sensitive to the atmosphere and humidity. Copper coins with green gunk on them are unacceptable to me.

[jom]

As for an MS-68, there is no way that a copper coin can grade MS-68 and have an obvious spot.

 

You're right but evidently an MS70 can...just ask PCGS they'll tell you.

 

jom

[BillJones]

As for an MS-68, there is no way that a copper coin can grade MS-68 and have an obvious spot.

 

You're right but evidently an MS70 can...just ask PCGS they'll tell you.

 

jom

 

To be fair I'm sure that coin turned in the holder, but they were certainly slow on the uptake to remove a certain 1963 Proof 70 graded cent from the market.

[JIM F.]

Back in 1974 there was an article in one of the coin magazines (Coin World??) about how to prevent a copper coin from toning. If my recollection is correct it was immersing it in benzene. So I took a couple mint rolls and applied this technique. I still have the coins, and did not go out of my way to store them other than in coin rolls -- paper ones at that! As of today they are bright cherry red without any signs of spots or toning.

 

Maybe this technique will come into practice for those with red coppers as my limited experience shows that it worked on my 1974-D Lincolns- 40 years later and no spots.

 

I have a degree in chemical engineering, but have no idea why/how this process prevents toning. I should have thrown away the coins and kept the magazine.

 

 

 

 

 

[Nutmeg Coin]

Spotted copper coins trade at a discount, and as far as I know CAC will not sticker them, even if they are otherwise good for grade; that remains an eye appeal/problem category quite apart from the A/B/C grading categorization within a particular grade.

[Raisethis2]

Welcome to the forum.

 

Spotting on copper usually results from exposure to some element in the atmosphere the raw copper didn't like. Accordingly, once a spot begins it's near impossible to completely arrest the cause and so over time things just get worse.

 

 

[Kurtdog]

It's like an eye-magnet, it disrupts the eye movement through the coin. That, in turn, disturbs how you feel about the coin.

[Conder101]

I have a degree in chemical engineering, but have no idea why/how this process prevents toning.

Seems fairly obvious. The benzene will not react with the metal and like acetone it works like an organic solvent to remove any contaminants from the coin. Then as long as itis stored in a stable low humidity environment it will most likely not change.