The grade is still UNC. The grade is the amount of wear and marks on a coin. Look at it this way, if you take a new car for a test drive, and put 20 miles on it, is it still new???? Yes, it is. Still has all the characteristics of a car fresh from the assembly line, the little mileage is incidental. But, if you were to take a 5 mile test drive, and accidentally clip a light post and scratch the fender, then it isn't new anymore, is it?? It now has evidence of usage and wear.