First, I think to qualify FDC with A or N is a complete nonsense - AFDC is merely UNC (or a slightly flawed PROOF) and should be described as such. In the modern era, FDC normally applies only to proofs, as currency coins will ALWAYS have imperfections, unless it's those BU specimens sold by the Mint. FDC should describe a coin with no flaws. No defects, knocks, bag marks, scratches, weak strike, marks, wear, rubs, cleaning, etc. However, do be aware that FDC has never applied to toning; but if a dealer described a badly toned coin as FDC I would consider it a bit cheeky! 1973 FDC proof set for sale ~ slightly toned I own the one UNtoned 1973 set!! Make that two. I own an untoned set too. At least, it was last time I looked.