And that's exactly what it is - tarnish, better known as toning. But looking at those I wouldn't worry about it much. The coins look to have been...
These are the best 2 books on grading that there are - http://www.amazon.com/Official-American-Numismatic-Association-Standards/dp/0794819931...
Not really. If they did then you could trace and date the slabs and thus track the grading practices and changes in their grading standards. Not...
Need to see the rev also to identify it.
Other than the links provided to threads on the forums, there is no web site that lists the various varieties of slabs over the years. And if you...
Separate names with a comma.
