Die clashing is frequently seen on Franklin half dollars. In fact, the Mint was clearly self-conscious of this at the time, struggling to file or polish them away. Clashing can appear in a number of locations, due to variations in die position, die alignment, and striking pressure; but only some are desirable to collectors. The strongest and most popular clashes can leave an imprint of the eagle’s wing over Franklin’s mouth, creating the famous “Bugs Bunny” varieties, and sometimes even a nearly complete outline of Franklin’s bust on the reverse. Many of the Bugs Bunny varieties actually do resemble the classic cartoon character, or even a vampire, and it is easy to see why these are the most popular clashes.
However, some of the other obverse clashes have become collectible in and of themselves. And, for variety attribution, it is important to learn the jargon for all parts of the design that can show clash marks.
Bugs Bunny Clash
Created when the wing feathers of the eagle clash over Franklin's mouth. Clashing can range from a full impression of the wing to a few spikes on or around the mouth.
Goiter Clash
A Goiter Clash is an area of raised metal somewhere along the edge of Franklin’s neck. Typically, it shows under the chin and at the base of the neck, but can run the entire length of the neck. Do not confuse with the “Goiter Die Chip,” which is in another section. These Goiter Die Clashes are highly collectible by themselves, though many of them are found in conjunction with more popular Bugs Bunny clashes, and are thus overshadowed.
Collar Clash
A collar clash is directly related to a goiter clash, but this manifestation is a distinct angular clash at the base of the neck. It actually makes Franklin look like he is wearing a collared shirt. If it gets any bigger, it generally becomes known as a goiter.
Horn Clash
Directly related to the Goiter and Collar Clashes, this time the raised area appears in the open field, between the date and the neck. These can be very dramatic.
Letters Behind Head
Sometimes, letters of E PLURIBUS UNUM imprinted in the field behind Franklin’s head. While often seen in combination with known Bugs Bunny dies, the FVI does identify a few of these that are known and collected on their own merits.
Crease Through Nose/ Spiked Nose
The right edge of the Liberty Bell could sometimes make a heavy crease or spike through the bridge of Franklin’s nose. Sometimes it doesn't crease the nose and instead shows as a spike coming up from the nose. These are not typically collected in and of themselves, as they are usually accompanied by other clash features that are more popular, but again, there are exceptions.
Nose Clash & Bulge Under Eagle
Franklin's nose can imprint on the reverse. Often, it will show only as a spike coming out of the bell, or as a bulge under the eagles left-facing foot. The bulge under eagle is probably the most commonly seen clashing on Franklin halves. These two features are not readily collected on their own merits.
Capped Bell
The cap is a raised dome of metal that hovers over the right shoulder of the bell. It was created by a clash of Franklin's neck. This same area of the reverse is what creates the goiter clash on the obverse.
Hair Through E PLURIBUS UNUM
Many dies show a wavy clash line of the hair line behind Franklin's head running vertically through the motto on the reverse. These can be markers of other clashing, or stand alone, but are seldom sought after by themselves.