Rock Identifier
Tumbled amethyst (Quartz (SiO₂), purple variety known as amethyst) — mineral
mineral

Tumbled amethyst

Quartz (SiO₂), purple variety known as amethyst

AI-generated identification · may be incorrect

Hardness 7 Mohs; translucent purple-and-white color with a vitreous luster and trigonal crystal structure. The rounded, glossy surface suggests it has been tumbled.

Identified More mineral
Explore Tumbled amethyst in the encyclopedia →

Identify your own rocks.

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

Physical properties

Hardness 7 Mohs; translucent purple-and-white color with a vitreous luster and trigonal crystal structure. The rounded, glossy surface suggests it has been tumbled.

Formation & geological history

Amethyst forms when iron-bearing silica crystallizes in cavities, commonly in volcanic rocks; its purple color develops through trace iron and natural irradiation. Deposits range in age from ancient to geologically recent.

Uses & applications

Used for jewelry, ornaments, and mineral collections; it is also a popular inexpensive tumbled stone.

Geological facts

Amethyst’s color can fade with prolonged exposure to strong sunlight or heat. The photo supports a likely identification, but does not show enough detail for confirmation.

Field identification & locations

Look for purple quartz with a glassy luster and hardness sufficient to scratch glass; amethyst commonly occurs in geodes in Brazil and Uruguay, as well as elsewhere. The pictured stone appears small and polished.