@jmlanzaf said:
ALL album toning is artificial in the sense that contaminants (sulfur) in the cardboard cause the formation of silver sulfides on the surface.
Isn't all toning due to a coin being in the presence of contaminants?
Yes. A coin reacts proportionately to the environment that it is placed into. A coin stored in a vacuum will not fare the same as like coin kept near one of those hydrogen sulfide emitting thermal features in YNP. Both are natural results of the exposed/storage conditions.
Comments
Yes. A coin reacts proportionately to the environment that it is placed into. A coin stored in a vacuum will not fare the same as like coin kept near one of those hydrogen sulfide emitting thermal features in YNP. Both are natural results of the exposed/storage conditions.
Would say natural - rim in contact with cardboard or whatever.
I like the earlier toning before it turned blue.
Collector, occasional seller