How amethysts are forming?
Amethysts are a variety of quartz that form in volcanic and metamorphic rocks. They are typically formed when silica-rich fluids mix with gases that contain trace amounts of iron and manganese, and then cool and solidify. The iron and manganese ions in the fluid become incorporated into the crystal structure of the quartz, giving it its purple color. The depth and temperature of the fluids and gases, as well as the presence of other minerals, can all affect the final color and size of the amethyst crystals that form.
How amethysts are found?

Amethysts can be found in a variety of geological settings, including volcanic and metamorphic rocks, as well as in geodes and alluvial deposits. Some of the most notable amethyst deposits are found in volcanic rocks such as basalt, where the mineral forms in gas cavities or as crystal-lined vugs. Amethysts can also be found in geodes, which are spherical or oval-shaped rocks that contain a hollow cavity lined with crystals. Geodes can form in a variety of environments, including volcanic and sedimentary rocks. Amethysts can also be found in alluvial deposits, which are gravels and sands that have been transported by running water and deposited in a new location. Some of the most notable amethyst deposits are found in Brazil, Uruguay, Argentina, Mexico, Canada, Africa, Russia, and Europe.