It's the Fragmented Hat Variety. As the story goes, Liberty's cap was getting old and a gust of wind came up suddenly. This caused the tip of the back of her cap to fragment. Or so I'm told.
Well, I admit, I assumed it was a fake. Those "bubbles" are on all the 1833 FS-901 capped bust quarters! It has repunched letters on the reverse at OF, which also threw me off, because I assumed it was the O/F reverse of an 1834. But, in fact, it's a variety similar to this 1833 fs-901. Browning 2. I learned something new today! (But so wonder what caused the raised metal in those areas of the obverse??)
Those raised marks appear in areas of the devices as well. My guess is the die rusted due to improper storage.
The raised bumps are due to die rust. This coin also has the shield clash marks at the ear. Edit: Oh yes, and a very nice coin. I like it!
Here's a close up of the repunched reverse letters. See the other "A" to the left of AMERICA? And the F between the OF?
Honestly, I knew I'd seen this one before, but I didn't remember when/how and had to go back to Square One to refamiliarize. With a memory like mine, one learns early to research quickly and often.