I use the following:
NEW--Unused
VGD--Very Good, as to square edge with only minor nicks & no loss of
gold in the hot stamp
GD--Good, but rounded edge, some loss of gold in hot stamp
WRN--Worn, loss of depth and little gold in hot stamp, rounded edges,
may have to hold to light to read
DAM--Damaged, large chip, crack, inlay missing, scratch or scrape
CAN--Drilled, notched, or overstamped with the intent to cancell (not done to revalue denomination)

Hope this helps