for a nuke you only need uranium, dmg, and titanium, or diamond for casing, in this game that's pretty much the most size efficient death device you can make, the one using diamond is way more destructive but needs ambient heat.
1. plutonium OR uranium. which-ever you prefer. 2. deuterium is optional 3. use titanium not metal 4. you usually wouldn't have C4 OR TNT, but those are optional.
Obviously this isn't a nuke, a nuke would be using dmg and uranium, but this is the first time I've ever seen anyone managed to do a mushroom cloud, well done.
the problem by making this is every time i detonate it the nuke touches the ground too late so its less impressive it touches the ground but the ball is already huge