I have all but three of the Morgan dollars. None are graded and I have had them for decades. How does toning affect grading and would they even be considered? This 1880 O is an example. Could it be graded?
They grade toned coins all the time. How they do it and what their opinion is based on is one of the great mysteries of the universe for some of them. That one is nice, but I don't know how or what they base their grades on some of them.
If you've had them for decades, why would you want to cert them? Your eyeballs have enjoyed them for years. Why get a little piece of paper enclosed in plastic to obstruct part of your view, especially with your pockets a little emptier?
Toning will not affect whether it can be graded or not (unless it is artificial). The toning will primarily impact 2 factors of grading - the luster, and the eye appeal. A light bit of toning helps to reinforce the originality of the coin, and is considered desirable. Heavy toning may be undesirable because it can diminish luster and hide contact marks (or signs of cleaning). If the toning is too thick, it can mute the luster, and for some people, strong luster is their preferred look. Toning can have a wide range of eye appeal, from offputting, neutral, or beautiful. Rainbow toned coins may actually increase the grade because of the eye appeal. The coin you show I would describe as "neutral".
I don't think I want to cert them. I was just curious. My collection is based upon eye appeal, as you suggested.
I have several children, grandchildren and great grandchildren that are starting to collect and I want to be able to answer the questions that I had not needed answers to. Thanks for the feedback.
