gemstone

Tumbled amethyst

Quartz (SiO₂), purple variety colored mainly by iron impurities and irradiation

AI-generated identification · may be incorrect

Hardness 7 Mohs; vitreous luster, purple coloration, translucent body, and conchoidal fracture; trigonal crystal structure before tumbling, with no cleavage. Specific gravity is about 2.65.

Identified September 5, 2026More gemstone →

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Physical properties

Hardness 7 Mohs; vitreous luster, purple coloration, translucent body, and conchoidal fracture; trigonal crystal structure before tumbling, with no cleavage. Specific gravity is about 2.65.

Formation & geological history

Forms in cavities of volcanic rocks when silica-rich hydrothermal fluids crystallize quartz, commonly alongside agate and calcite. Most amethyst formed in ancient volcanic environments, often hundreds of millions of years old.

Uses & applications

Used for beads, cabochons, carvings, ornaments, and mineral collections; gem-quality material is used in jewelry. Tumbled pieces are generally decorative or metaphysical objects.

Geological facts

Amethyst is the February birthstone and one of the most recognized quartz varieties. Heating can turn it yellow-orange, producing citrine or ametrine-like colors.

Field identification & locations

Identify it by its glassy luster, purple color, hardness, and lack of cleavage; glass may show bubbles and scratches more easily. Major sources include Brazil, Uruguay, Zambia, and Bolivia.