1981-D Lincoln Cent - Does It Go Full Brown?

Funny "panzaldi", I like your post. The reality it is: The coins collect involve the science at all levels, from mint production till the end collector and the preservation of the values (could be monetary or simply passion). the last study I post is all cooper coins and bronze coins by this method comeback to the initials stage and color. It is not invasive and give the really look of the artifact. Only thing it is must be preserve after in proper matter, for this reason I work to develop the system that the coins must be vacuum close. The TPG's do not agrees because like this they loose in business, but us the collectors we preserve the beauty and our passion for generation to come.