Fun to imagine on geophysical length scales that each dot of gold-sulfur rich complex in the diagram could represent like several orders of magnitude more gold than has ever been mined out of the Earth to date.
(No idea whether that is the right sizing, but I could totally imagine it being the case)
edit:
"...The estimated amount of gold ever mined is around 212,582 tonnes, according to the World Gold Council. This is roughly equivalent to a cube of gold that's about 22 meters on each side..."
Fred Hoyle theorised (or popularised other peoples theories) that it squeezed like water from the interstitial spaces in the rock under geological time and pressure. I've got a book of his from the 60s discussing planetary formation which mentions it.
My layperson understanding was that all of the surface gold (i.e. available to humans, not in earth's core) was delivered here via comets/asteroids.
The explanation I received was that the densest atoms (e.g. gold) migrated into the core over billions of years (because: gravity; gold is twice as dense as lead).
What I read (in the past few months…don't have a link handy) is that gold is highly insoluble, but quartz's electrical properties can help seed crystallization of the atoms from (rock) solution (which is why it tends to appear with it).
(No idea whether that is the right sizing, but I could totally imagine it being the case)
edit:
"...The estimated amount of gold ever mined is around 212,582 tonnes, according to the World Gold Council. This is roughly equivalent to a cube of gold that's about 22 meters on each side..."
https://www.gold.org/goldhub/data/how-much-gold
https://www.usgs.gov/faqs/how-much-gold-has-been-found-world