Uranium

Uranium (Ore)
Uranium will spawn in your underground world shortly after you have defeated the Moonlord.

It is a Hard mode Ore that is as rare as titanium would be. It emits a green radioactive glow. If you step on the ore without the equipment needed, it will burn you. Obsidian accessories don't work either. When destroyed, it has a 5% chance to drop an item called Radioactive Waste, which could be used for crafting

It could spawn anywhere in the map, even in Hell unlike most ores. If it is in any type of liquid, the liquid would steam up and bubble, A easy way to spot it.

Uranium Bars
Crafting Recipe

8 Uranium in a Hallowed Forge = Uranium Bar.

 'It flows with radioactive energy'

When placed it glows a light green. This doesn't count as a light source for NPC Housing.

Can only be in a recipe that is crafted in a Hallowed Anvil.