[weiping2007]

is nuclear a stone or a metal?
and how does people go and take the nuclear?
if they take the nuclear, they will get radioactif from the uranium. and this will cause side effect.

sorry my english not so good

[Bakegaku]

I think you misunderstood something in some translation.  Nuclear isn't a material.  Nuclear energy is energy that comes from the nucleus of an atom.  A nuclear material is a material from which this energy can be obtained.

What is your native language?  I'd suggest searching Wikipedia, as they have a variety of other languages other than English.

[ojoogun]

 The nuclear is an ability or energy which is being generated from an atomic nucleus.This nuclear energy is divided into two which are, NUCLEAR FISSION AND NUCLEAR FUSION.
But this nuclear energy is a radiation emitted from the source-Transition metal.So nuclear is not a metal nor stone but a by-product of nucleus of an atom.
And some of elements that emitted it are Uranium,Thomptium,Helium,Neptunium...
Therefore the nuclear energy is released by either broken down of simpler atoms or catabolise the atoms with the aid of energy supplied.
   

[P]

is nuclear a stone or a metal?

As Bakegaku said  -  the word NUCLEAR does not describe a substance or a material like wood stone or metal.  If something is 'nuclear' then it means it is 'of the nucleus'  i.e. 'nuclear energy' is 'energy from the nucleus'.