What is the definition of an FBL Franklin half dollar?

Mint State certified Franklins will have an “FBL” on the holder when the Franklin half dollar certified offers a solid strike. The “FBL” designation stands for “Full Bell Lines”. The bell lines on the Liberty Bell on the reverse of the Franklin half dollar have to be completely undisturbed solid bell lines. If the bell lines are weak or broken in any areas the full bell line designation will not be given. If there are any bag marks/scratches through the bell lines the FBL designation will not be given. Finding mint state Franklins with full bell lines is tougher than one might think.

There are two sets of horizontal bell lines on the Liberty Bell on the reverse of the Franklin half dollar. Both sets of bell lines need to be bold and undisturbed to be designated FBL by some grading services, while others only use the bottom set of bell lines to determine the FBL designation. Usually when a Franklin half dollar is poorly struck the bottom set of bell lines will be on the weaker side as this is the highest point on the Franklin half dollar. Check out the following pictures provided and look closely at the bell lines. Try to decipher for yourself which examples should be designated FBL or NON. The answer is under each picture.
 
NON FBL
FBL
Some issues in the Franklin half dollar series offer mushy and weak strikes making them tougher to locate with full bell lines. The San Francisco bunch being the weakest of all three mints. The rarest Franklin in the series with full bell lines is the 1953-S. Finding an example in any grade in this date is extremely rare and a coin I have seen to continue to climb in value over the years. I strongly recommend tucking any 1953-S Franklin away you can find with full bell lines.
The top five rarest Franklins in FBL to date are in order by date starting with the 1953-S, 1952-S, 1963-P, 1949-S and ending with the 1962-P. These dates right here have the lowest examples certified in all grades of FBL. I bet some of you were thinking the toughest issues would be the earlier dates! That is not the case here in this series. Throw finding examples with attractive eye-appeal and spot-free, haze-free surfaces to the mix and the rarity continues to climb through the roof.