Bust Halves Of 1809

Only things that stick out in the RedBook to me are the bust itself on the 1809 looks much larger/rounded. There is a hair curl above the button on the 1809 that's not on the 1807.

The eagle looks like it has different talons for sure. Not sure if there's more of a "forehead" on the 1809 but it looks like it....

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Paraphrased from Overton v.4 p.161

obverse changes:
bust figure made smaller with smaller face
jaw line better defined
cap is smaller with folds more pronounced
only one line on headband below liberty
bust more fully developed

reverse changes:
fuller left wing on eagle
shield wider
claws and talons longer

The objective was produce a more attractive coin with more detail and relief to counteract the weak or mushy appearance of the 1807 and 1808 half dollars.

The result was that the eagle's left wing is rarely well detailed in the feathers and the obverse hair is poorly detailed which is why many specimens are advertised as "weakly struck". Well preserved, well struck 1809s are difficult to locate and highly prized.