You are right, but I get a lot of questions about this subject. I had to shoot this video to clarify these issues. There are many topics in geological engineering, I will shoot educational videos on other areas of geology, don't worry.
Gold (Au) and silver (Ag) are part of a fascinating geological process, and understanding their origins involves diving into Earth's geologic history and the behavior of hydrothermal systems. Here's a breakdown: How Gold Gets into Hydrothermal Solutions Formation of Gold in Earth's Crust: Gold originates in Earth's mantle and crust. It was either present during Earth's formation or brought to the surface by meteorites during a period known as the Late Heavy Bombardment (around 4 billion years ago). Over time, gold became concentrated in certain areas due to magmatic and tectonic processes. Hydrothermal Activity: Gold is typically dissolved in molten rock (magma) as tiny trace amounts. When magma cools, it releases fluids rich in water, carbon dioxide, and dissolved elements, including gold. These fluids form hydrothermal solutions. The gold dissolves in these solutions because of high temperature, pressure, and the presence of sulfur or other elements that form gold-bearing complexes (like AuCl 2 − 2 − or AuHS). Transport: These hydrothermal solutions migrate through fractures, faults, and porous rocks in the Earth's crust, carrying dissolved gold along with other elements like silver, copper, and sulfur. Precipitation: Gold precipitates (comes out of solution) when the conditions of the hydrothermal fluid change-such as a drop in temperature, pressure, or pH, or when the solution mixes with cooler, oxygen-rich groundwater. The gold then crystallizes within quartz veins, sulfide minerals, or other host rocks. How Silver (Ag) Comes About Silver has a similar origin story to gold but behaves slightly differently due to its geochemical properties: Silver in Earth's Formation: Like gold, silver was present during Earth's formation and also delivered by meteorites. It is often found associated with gold in hydrothermal systems because both are "chalcophile" elements, meaning they tend to bond with sulfur and form sulfide minerals. Hydrothermal Solutions and Silver: Silver is more chemically reactive than gold, so it forms more diverse mineral species, such as argentite (Ag 2 2 S), galena (PbS with Ag inclusions), and native silver. Silver can be dissolved in hydrothermal solutions through chloride complexes (AgCl 2 − 2 − ) or sulfide complexes. Deposition: Silver precipitates in a similar way to gold when the hydrothermal fluid's conditions change. It often occurs alongside gold but can also form in distinct ore deposits known as silver veins.
We're seeing a lot about gold deposits lately!
You are right, but I get a lot of questions about this subject. I had to shoot this video to clarify these issues. There are many topics in geological engineering, I will shoot educational videos on other areas of geology, don't worry.
pretty cool.
Really cool. Can’t do the AI voice
Thank you.
Thank you.
Gold precipitates out of hydrothermal solutions?? How did the gold gets inside it? How did the element Ag come about?
Gold (Au) and silver (Ag) are part of a fascinating geological process, and understanding their origins involves diving into Earth's geologic history and the behavior of hydrothermal systems. Here's a breakdown:
How Gold Gets into Hydrothermal Solutions
Formation of Gold in Earth's Crust:
Gold originates in Earth's mantle and crust. It was either present during Earth's formation or brought to the surface by meteorites during a period known as the Late Heavy Bombardment (around 4 billion years ago).
Over time, gold became concentrated in certain areas due to magmatic and tectonic processes.
Hydrothermal Activity:
Gold is typically dissolved in molten rock (magma) as tiny trace amounts.
When magma cools, it releases fluids rich in water, carbon dioxide, and dissolved elements, including gold. These fluids form hydrothermal solutions.
The gold dissolves in these solutions because of high temperature, pressure, and the presence of sulfur or other elements that form gold-bearing complexes (like AuCl
2
−
2
−
or AuHS).
Transport:
These hydrothermal solutions migrate through fractures, faults, and porous rocks in the Earth's crust, carrying dissolved gold along with other elements like silver, copper, and sulfur.
Precipitation:
Gold precipitates (comes out of solution) when the conditions of the hydrothermal fluid change-such as a drop in temperature, pressure, or pH, or when the solution mixes with cooler, oxygen-rich groundwater.
The gold then crystallizes within quartz veins, sulfide minerals, or other host rocks.
How Silver (Ag) Comes About
Silver has a similar origin story to gold but behaves slightly differently due to its geochemical properties:
Silver in Earth's Formation:
Like gold, silver was present during Earth's formation and also delivered by meteorites.
It is often found associated with gold in hydrothermal systems because both are "chalcophile" elements, meaning they tend to bond with sulfur and form sulfide minerals.
Hydrothermal Solutions and Silver:
Silver is more chemically reactive than gold, so it forms more diverse mineral species, such as argentite (Ag
2
2
S), galena (PbS with Ag inclusions), and native silver.
Silver can be dissolved in hydrothermal solutions through chloride complexes (AgCl
2
−
2
−
) or sulfide complexes.
Deposition:
Silver precipitates in a similar way to gold when the hydrothermal fluid's conditions change.
It often occurs alongside gold but can also form in distinct ore deposits known as silver veins.