An awesome 10th of a gram...
The YouTube channel PBS Space Time, in The Alchemy of Neutron Star Collisions
( https://youtu.be/MmgMboWunkI?t=624 )
summed up the topic thus:
"Neutron star mergers are likely the dominant source of most elements of atomic masses 44 and up, that includes most of the lead, silver, gold, rare earth elements and the radioactive stuff like uranium and plutonium also a good fraction of the molybdenum and iodine which are essential for your biology.
In fact, including the non-essential heavy elements your body masses something like 2ppm colliding neutron star material.
That's only a 10th of a gram or so, but it's a pretty awesome 10th of a gram.
It was, after all, synthesised on the rim of a black hole before surfing a wave of neutrinos into the nebula that would eventually collapse into our solar system... and those atoms would eventually find themselves part of a lifeform that would figure out the very time and distance of their formation."