TMZ reported, and apparently stands by it, that it was something like a shard of glass. I believe their source was US Secret Service themselves.
Trump said twice now (at least) that a bullet did nick his ear. There's also a photo of the bullet (which people are saying is legit, but I don't fully believe that, but whatever) apparently on a path straight to his head right before he moves.
I assume the FBI will eventually release a full recreation of the events with the trajectory of the bullet. That'll be the most reliable source.
My guess is it was probably glass or something because what the fuck and Trump has every incentive to lie obviously. Ear cut from glass is far far far less cool than a bullet grazing you
I heal better, more perfectly, I have just the best healing. My ear grew back just like it was, even better! I have tremendous healing. See? You can't even tell I was shot!
Here's the TMZ comment and statement from Secret Service. They haven't taken it back or updated it with a correction. Only stated that Trump claims it hit his ear.
A SOURCE WHO HAS SPOKEN WITH A MEMBER OF THE SECRET SERVICE TELL TMZ, TRUMP WAS NOT HIT BY A BULLET. RATHER, A BULLET HIT HIS TELEPROMPTER AND THE GLASS STRUCK HIM BY THE EAR