I wanted to give a public thanks to @BadThad. I asked his advise, which he gracefully provided, and that helped me salvage this 1930-D. The pictures are admittedly poor. The Before is from the dealer on eBay. The coin is in a SEGS holder. I ignored the grade and bought. The surface really looked as bad as shown here. After cracking it out and giving it an acetone treatment, it now looks like this; the spots, marks, and general crumminess are gone. (I had a color balance issue with my photo, but the color should be the same as above. The point is to show the surface improvement, after all.)
Great job! Graduation comes when you get it back into an MS-65 holder. There is some residue under the "D" and at 10 O'clock. The acetone may have left a "blue" color on the left rim.
Thanks! Now that I have broken the ice, I won't be so timid. I may give it a bit more of a soak. I am working on a year set of Lincolns through 1990 and have all but 1914 and 1922. I have most as raw coins in airtites. Some are graded and encapsulated. And I have a full Dansco from 1934-1990. So I can't say where I'll end up. I have a lot of Lincolns I love but may never be graded. But this coin ended up beautiful! Very happy!
LOL. If I had thought to take a "Before" picture, you would have seen how cloudy it was. The seller's original pics were nice enough that I felt it was OK to buy, but the actual coin in the holder was pretty ugly. I did not expect such a transformation or I would have documented it better. I may try to document a few of my attempts if my learning process can help others. I am hoping to learn how to reverse some bad things that may have happened. Some of my coins were bought as a BU set where the original collector apparently talked over the coins and left spots, as well as occasionally pressing them into the Dansco with a bare thumb. Sigh. So I will have a lot of practice.
