From ancient times to famous gold rushes, gold was first discovered in placer deposits. Placer gold occurs when host rock weathers and releases gold particles that travel downslope to a hillside, canyon mouth, or streambed.
Today most gold comes from hard rock deposits where gold is disseminated or associated with other metals and mined either through open pit or underground mining. Gold deposits form when gold is dissolved in hot pressurized fluids deep in the crust, and then transported upwards on fissures and cracks where it is deposited closer to surface.
View Part 4: Gold as an Investment