At or NT?

[walmann]

Well written where the disagreement  is in the definition of  the words we are using.

Patination refers to a film of oxide on metal. Oxide is the combination of oxygen atoms with the atoms of the metal. Tarnish refers to the process of oxidation. Often times this is assisted by sulfur in the air. Both are reference to the interaction of air with the metal. This can of course act as a protective layer from further oxidation just as a layer of rust may protect metal beneath. Metals such as gold and platinum are resistive to natural oxidation, hence natural toning is absent.

Oxidation is gradual and is one just one of many possible sources of corrosion, but corrosion it is, just gradual and less damaging to the metals integrity. Over long periods of time it is may become more damaging.

 Many times toning is the result or not just oxidation, but other agents interacting with the metal. The involvement of these other agents are where I would argue are not would be considered natural toning.

You mentioned scientists, some state toning is tarnish and some state it is patination, both terms refer to the oxidation process, oxygen atoms combining with the metal. The issue with many forms of toning is that more than oxidation has contributed to the resulting "tone" of the coin.

The coin posted in my opinion is toned due to more than just the oxidation process, some other agents were involved.

We will have to discuss how royalties will be divided on the book proceeds and selecting a ghostwriter for myself.