Hi, Here is my 1785 1/2P Vermonts (not Vermontis I think). It's more worn than I'd like, and it's holed ("sigh"). That being said, you can tell what it is. My armature eye would give it a grade of 3 and I'd put the value somewhere in the $200 to $250 range. How on or off target am I? All opinions welcomed - this is how I learn. Thanks!
What a spectacular slice of American history. And frankly, I have no working knowledge of this colonial piece. I am betting the design is inspired by the Nova Constellatio design that was issued two years prior. Your dad certainly collected some fine historical examples and while I cannot offer anything useful about the piece I did take the verbiage below from the PCGS website: The 1785 VERMONTIS is a spelling variant of the 1785 Landscape Type Vermont Coppers (the other two spelling varieties are VERMONTS and VERMONTENSIUM). The pressure to collect all three of these varieties increases the value of the VERMONTIS variant because it is represented by only one die combination (Ryder 4). High grade examples are very rare -- the best is the Gem example that currently resides in the Bennington Museum in Vermont. The Ford:17 About Uncirculated was another notable example. The key to collecting the 1785 VERMONTIS (and all Vermont Coppers, for that matter) is to locate examples that have clean surfaces, a problem-free planchet, and a nice, chocolate-brown color. The VF30 illustrated above features two out of three.
These things are tough to put a grade on, obviously unevenly struck, decent detail on half basically none on the other half. It's an RR2, one of the more common landscape varieties, and they are often unevenly struck. As far as value, I think your estimate is kind of high considering the hole, of course I may just be cheap! I have a few Vermonts but don't actively collect them, I've been working on Connecticuts lately.