Originally Posted by
rickair7777
Not quite. Very rare but it happens.
That low on the periodic table, pretty much anything will occur in nature in very specific circumstances... the right geology will result in proximity of heavy elements and neutron bombardment. Statistically it will happen eventually, once a precursor is formed the decay process is on rails and inevitable.
For practical purposes, it's correct that you need to breed Pu-238 to acquire any useful amount of it. You'd have to mine and refine literally mountains of rock to get the slightest trace of the natural stuff (which is of course utterly indistinguishable from man-made).
That is contrary to what Glenn Seaborg told me, face to face. For Pu-238, there is no naturally occurring. I respect you, Rick, but I respected Glenn on this topic, even more.