Amethyst

Chemical Composition
Formula: SiO₂ (Silicon Dioxide)
Color: Shades of violet to purple (due to iron impurities and natural irradiation)


Physical Properties
Hardness: 7 (Mohs scale)
Cleavage: None
Fracture: Conchoidal
Luster: Vitreous
Density: ~2.65 g/cm³


Origin and Location
Major Sources:
Brazil (Rio Grande do Sul)
Uruguay
Zambia
South Korea
Russia
United States (Arizona)


Varieties
Siberian Amethyst – Deep purple with red and blue flashes
Rose de France – Pale lavender to light purple
Chevron Amethyst – Banded pattern with white quartz

Uses
Jewelry: Rings, necklaces, earrings
Decorative: Geodes and carvings
Spiritual: Used in meditation and healing practices


Curiosities
The name "Amethyst" comes from the Greek word amethystos (ἀμέθυστος), meaning "not intoxicated." Ancient Greeks believed it prevented drunkenness.
Heating amethyst (around 400–500°C) turns it yellow or brown, producing citrine.
Some amethysts fade when exposed to direct sunlight for long periods.


Formation Process
Amethyst forms in silica-rich volcanic rock cavities through slow crystallization from hydrothermal fluids. Iron impurities and natural radiation give it the purple color.

History and Discovery
Used since ancient Egypt for amulets and carvings.
Prominent in Greek and Roman culture as a symbol of sobriety and protection.
The largest amethyst geode, the "Empress of Uruguay," measures over 3 meters and weighs around 2.5 tons.


Optical Properties
Pleochroism: Displays shades of purple and violet depending on the angle of light.
Transparency: Transparent to translucent


Mineral Classification
Class: Silicates
Group: Quartz