Answer:
What can you share and still have all for yourself?
I have one, you have one. If you remove the first letter, a bit remains. If you remove the second, bit still remains. If you remove the third, it still remains.
Each of these ends in a kettle full of precious metal and the double variety is quite awesome
What kind of nut is empty at the center and has no shell.
Golden treasure I contain, Guarded by hundreds and thousands. Stored in a labyrinth where no man walks, Yet men come often to seize my gold. By smoke I am overcome and robbed, then left to build my treasure anew
Almost everyone needs it, asks for it, gives it. But almost nobody takes it.