mineral

Amethyst

Quartz (Silicon Dioxide with iron impurities), SiO2

AI-generated identification · may be incorrect

Hardness: 7 (Mohs scale); Color: Pale violet to deep purple; Luster: Vitreous/Glassy; Crystal structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Pale violet to deep purple
Luster: Vitreous/Glassy

Identified July 1, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Pale violet to deep purple; Luster: Vitreous/Glassy; Crystal structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Formation & geological history

Forms in hydrothermal veins or inside volcanic geodes (amygdules) when silica-rich water cools. The purple color is caused by trace amounts of iron radiated by surrounding rocks. The region of Hyderabad (17.5°N, 78.3°E) is part of the Deccan Traps and surrounding Precambrian terrain where quartz varieties are common.

Uses & applications

Widely used for semi-precious jewelry, ornamental carvings, and as a popular specimen for mineral collectors. Historically used in amulets and drinking vessels.

Geological facts

The name comes from the Greek word 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness. It is the birthstone for February.

Field identification & locations

Identified by its purple color and hardness (it will scratch glass). In the field, look for hexagonal crystal points or purple masses inside basaltic or granite cavities. While found globally, significant deposits exist in Brazil, Uruguay, and India.