So the recent neutron star merger event showed that most of the heavy elements (gold, platinum, uranium, etc.) are produced in kilonovas. But with neutron star mergers so rare, there can't be that many kilonovas. Prior to this I always used to think they were mostly produced in supernovas. The chances that a solar system was seeded by a supernova seem much higher than one seeded by a kilonova. What proportion of heavy elements are produced in kilonovas vs. supernovas?