Answer: Gold minerals form in hot rocks in and around volcanoes. Low sulfur, gold-bearing hydrothermal fluids form when hot rocks heat ground water.
Explanation: Scientists believe all the gold on Earth formed in supernovae and neutron star collisions that occurred before the solar system formed. In these events, gold formed during the r-process. Gold sank to the Earth's core during the planet's formation. It's only accessible today because of asteroid bombardment.