Knowing Ceobe, she’d probably do this and survive relatively unscathed.

Given that someone did a taste test on uranium and reported it's slightly sweet (more like the radiation activates your sweet tastebuds, but...) I'd think she just thought it's a somewhat tough, black candybar.

Also nope, real uranium rod doesn't glow or shine. Also nope, radioactive materials aren't used in Terra for energy generation so there's no way you can have a purified, refined uranium rod. There's one mention on the event that Rhine Lab develops an atomic clock (but that only works by measuring the radiation rate) and there's that other event that mentioned a faction tried to develop a Terran version of nuclear fission but with Originium instead of radioactive material (of which Ka'ltsit shut that down).

Don't tell her Originium has even more calories.

Uranium is harder than titanium iirc so Ceobe must have really strong teeth to take out a huge chunk with one bite like she did.