Do you think the slab insert caused this toning?
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These are two new additions to my PF roosie collection. The first one is a 1958 graded PF-68 the second one is a 1963 graded PF-68 cam. Both coins are NGC. The toning looks alot better than the pictures show (these are just some quick pics) the toning on the 58 is a nice purple the 63 is mostly blue. I think the toning was caused by the slab they are in the old NGC holder where the insert isn't seperate from the coin I included a picture of the slab. The reason i think the slab caused it is because the coins are toned on the top and only on the Obv. the same place as the paper. Am i right or wrong in assuming that the slab toned the coins?
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Comments
Brian.
The concern though is that how long is enough for these patterns? How much toning is TOO MUCH?
They might be getting ready for an intercept holder?
<< <i>wrong move >>
He also is a firm believer that the inserts tone (harm) coins- especially NGC and then followed by PCGS.
peacockcoins
I am at that crossroads and mbiker looks to be also.
A perfect question for Mr. Hall.
<< <i>A perfect question for Mr. Hall >>
I agree i'm usually not on here Tuesday nights so you'll have to ask the question.
When I was working at NGC, I think I was told that at least two different chemists (or similar type experts) were consulted. They tested the holders, and grading labels, including the ink that was used on them, to make sure that they were inert. We were told that they were. I don't know what I can say, beyond that.
those dimes had something unusual on the surface that reacted w/ the vapors leeched out of the slab
all plastic produce gases - even "inert" plastic. it's a question of which plastic is more inert than others. i suspect the chemists that coinguy1 refers to meant their plastic is inert w/ respect to specific metals - but IF metal had something foreign on the surface, a chemical catalyst so to speak, it might actually encourage a chemical reaction.
all just a theory, i have no proof whatsoever
K S
Here's a clearly bag toned Morgan BUT it has peripheral tone on both sides. Text
Another strange peripreral: Text
I've had this one a number of years and watch the toning grow bigger: Text
Another bag toned with peripheral tone. The obv of this coin is next to the slab and the rev has air space between the coin & slab: Text
This crescent matches the angle of the coin in the holder, it's toned where the coin is away from the slab but where there is no air gap the it's untoned. It's not a crescent from another coin laying on top of it in a mint sack. Text
These coins are not flat in the holder & seem to tone in the holder where there is room for air and do not tone where the coin is against the slab.
Just post on the Q&A now... he will review it on Tuesday, then reply... you can post there anytime, the Tuesday bit is just when he has designated time to reply.
Jeremy