This is a BB-110, a particularly rare variety for 1798. I think the pattern of nicks, though, confirms this as a coin sold in a NGC holder at the Sept. 17 2015 Heritage Auctions sale at the Long Beach Expo. Whoever sold it to you cracked it out of its holder to hide its Details grade from you.
http://coins.ha.com/itm/1798-1-larg...otPosition=0And it looks like artificial toning was added since that sale.
Edited by philadelphian
02/14/2016 9:01 pm