Thoughts on Grading
Colonial coin grading is a rather controversial topic, as it is in the field of early US copper coins, with two widely divergent thought groups - those that favor traditional standards, and those that favor third party grading.
Third party grading is, in many ways, more liberal than traditional standards, usually on circulated coins. Pieces which routinely traded in the 1970s and 1980s as VF may well be slabbed as AU today.
There is also a substantial difference in the grading standards applied by the two largest grading services and it is very important to realize that their grades are usually, but not always, different for the same item. Sometimes very different.
As such, it is useful and important for any collector to view as many coins as possible in order to understand how these coins are graded by each third party service and how they are graded raw by the various auction houses.
Further, colonial coins exhibit significant vagaries of color, planchet quality, strike and centering, etc. and these attributes can impact the value of a coin as significantly, or even more so, than the numerical grade.
In short, numerical grades may vary widely depending on who is doing the grading, and in any case the grades tell only a portion of the story about the desirability and ultimately the value of a particular colonial coin.