[Frohickey]

There are two fissionable nuclear fuels, U-235, and Pu-239. U-235 is what makes enriched uranium, enriched. U-238 is what makes depleted uranium, depleted. Pu-239 is made from U-238.

If we would just start the process of recycling spent fuel rods again, we would decrease the amount of nuclear waste that has to be buried in Yucca Mountain. And recycling is good for the planet. :P

[rednesss]

Don't forget Thorium. Th-232 through neutron absorption and subsequent decays produces U-233 which is fissile as well. And Thorium is more abundant than Uranium.

[rednesss]

Also if I read your comment correctly, yes U-235 and Pu-239 are fissionable. But fast breeder reactors utilize U-238 as a fuel source and "breed" Plutonium at rates that produce it faster than the reactor "burns" it. That's the advantage of breeder reactors, you don't need to enrich uranium as naturally occurring uranium is 99.3% U-238 right out of the ground.