mineral

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Purple, violet, or lavender
Luster: Vitreous (glassy)

Identified March 15, 2026More mineral →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7 on Mohs scale; Color: Purple, violet, or lavender; Luster: Vitreous (glassy); Crystal Structure: Hexagonal/Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed in hydrothermal veins or volcanic geodes when silica-rich water cools. The purple color results from irradiation of iron impurities within the quartz structure. These specimens can range from a few thousand to millions of years old.

Uses & applications

Primary use is in jewelry, lapidary arts, and as a popular collector's mineral. Occasionally used in ornamental carvings and historically believed to have metaphysical properties.

Geological facts

The name comes from the Ancient Greek 'amethystos', meaning 'not intoxicated', as it was believed to prevent drunkenness. It was considered a Cardinal Gem until large deposits were found in Brazil in the 19th century.

Field identification & locations

Identify by its characteristic purple quartz color and lack of cleavage. Look for it in basaltic geodes or pegmatites. Common locations include Brazil, Uruguay, Zambia, and South Korea. For collectors, look for deep 'Siberian' purple hues and high clarity.

Other mineral specimens

See all

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral

Epidote

Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)

mineral