I've been a coin collector ever since I was perhaps 5 years old.  I'm getting on in the years so it's time to start divesting.  All of my auctions that you will see are items that I've held for decades.  For Mercury dime grading, pay attention to the cap wings on the Obverse and the lines of the fasces on the Reverse.  Most circulated showing significant wear will be graded just Good.  To be Fine then you need to see a little bit of definition in the wings.  On the Reverse the lettering will be a little bit more pronounced.  Then to reach XF condition you will see yet more definition in the wings but the big difference is that you can make out the lines on the fasces on the Reverse.    Nice die crack on the Obverse running through the 1 in the date, making the 1 look almost twice as long.  The 20D is a semi-key date.  This one has a nice error making it very tough to replicate.  I see no others in an advanced search for sold coins here in eBay.