I've always wondered, does the presence of heavy elements on earth (ones which are likely to have formed via neutron star mergers) indicate that a pair of neutron stars merged relatively nearby our sun when it formed? Or is there just a diffuse amount of these elements in typical protostellar clouds all over the galaxy?

Perhaps a simpler way of asking: are the heavy elements we find on earth typical for an average planet? Or does a planetary system have to be "lucky" enough to have formed near a neutron star merger, for it to have elements like gold in measurable quantities?