back to war! So, I said to you, hold on to every amount of unprocessed uranium....check this one out : uranium 235 is high enriched uranium (from nuclear reactors) however, if you have uranium 238 (pure uranium from mining) and you gather the two forms, you will have called in Physics, "critical mass" . This two forms, can have spontaneous fusion reaction, according to velocity, shape of the bomb, and temperature. And even more power, if it has a neutron reflector; a neutron reflector is a material like graphite or beryllium, because it makes a very high velocity to the explosion. So, the best shape of the bomb, is always cylinder, the most velocity it gets, imagine that you could use 200km/h or even higher velocity , Formula 1 , with a permanent magnet motor .