We are the second set (or more) of planets with a Sun at or around this location, (stuff left over from a previous supernova) otherwise we would not have the higher elements beyond iron around.
The transuranic elements (anything beyond Uranium 92) were discovered after we started playing around looking for fuel for the A bomb, some were created in the lab at first then found later in nature, some of the elements below Uranium are by products of radioactive decay of the higher ones.
If done right you can create gold out of lead just by removing some electrons, but it would be a bit radioactive.
There is evidence that around 2 billion years ago a super reactor took off, this created a lot of lower elements during the time it was active.
I would not have wanted to be around Africa at that time.
The Workings of an Ancient Nuclear Reactor
Is There Really A 2 Billion-Year-Old Nuclear Reactor In Africa?