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Why is gold often found with quartz and pyrite?

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A diagram showing the periodic table entry for gold, with the symbol Au, atomic number 79, atomic weight 196.96657, electron configuration, and labels for its properties as a solid transition metal with a face-centered cubic crystal structure. — gold The precious metal gold is a chemical element with the symbol Au. Its square on the periodic table details some of its properties, including its atomic weight, atomic number, and crystal structure.

Gold is frequently found in association with quartz and pyrite due to the geological processes involved in the formation of hydrothermal mineral deposits.12

Hydrothermal activity involves hot, mineral-rich water circulating through cracks and fissures in the Earth's crust. As these solutions move, they transport dissolved minerals, including gold, from deep within the Earth. When the water cools or undergoes chemical changes, these minerals precipitate out of the solution, often forming veins that contain both gold and quartz.13

Additionally, gold is commonly found in endogenetic deposits where it is finely disseminated within sulfide minerals, such as pyrite. Because both gold and pyrite can be deposited by the same hydrothermal solutions, they frequently occur together in these geological settings. While pyrite is sometimes mistaken for gold—earning it the nickname "fool's gold"—it is a distinct iron disulfide mineral that serves as a common host for gold particles in various rock formations.124