Gretsch Serial numbers can be confusing an unclear at times. Here are some helpful ways to date them from unique features of the era.
Fingerboad inlays:
The Half moon sometimes referred to as thumbprint or Neo-Classical appeared in 1957. These came on the higher end Gretsches. So if you see a Gretsch with these inlays you know it was made in 1957 or later.
Headstock Logo:
The slanted script logo was used pre 1950. In 1954 the T roof logo (long top line over the T in Gretsch) was used until around 1981.
Frets:
The Zero fret was used on all Chet Atkins Models starting in 1959, then in 1962 it was used on most all the other models like the 6120, Monkees . So Zero fret indicates post 1958.
Name Plates:
Metal name plates that were engraved started being used around 1958 and appeared on the White Falcon, Nashville (1966), White Penquin (1959). In 1965 it appeared on the Tennessean. Earlier models had no name plate so this is a good dating method when serial numbers are unclear.
Fake F holes on some models:
In 1957 Gretsch used simulated F-holes on the Country Gentleman, then in 1962 the F-holes are just painted on the guitar.
Padded Back:
The Padded Back was fazed in around 1962, and is a normal stock feature on the White Falcon, 6120, and 6122 and Country Club models.