mineral

Amethyst crystal cluster

Amethyst, purple variety of quartz (SiO₂)

AI-generated identification · may be incorrect

Mohs hardness 7; translucent pale-to-medium purple with vitreous luster and hexagonal quartz crystals. The specimen appears to be a natural crystal cluster, possibly on a light-colored quartz matrix.

Identified September 29, 2026More mineral →

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Physical properties

Mohs hardness 7; translucent pale-to-medium purple with vitreous luster and hexagonal quartz crystals. The specimen appears to be a natural crystal cluster, possibly on a light-colored quartz matrix.

Formation & geological history

Amethyst forms as quartz crystals in silica-rich hydrothermal fluids, commonly lining volcanic-rock cavities (geodes). Its age depends on its deposit; many major deposits formed in ancient volcanic rocks.

Uses & applications

Used in jewelry, decorative objects, and mineral collections; lower-grade material may be cut or polished for ornaments.

Geological facts

The purple color comes mainly from trace iron and natural irradiation. Amethyst is the traditional February birthstone.

Field identification & locations

Identify by its purple color, glassy luster, and hardness sufficient to scratch glass; common sources include Brazil, Uruguay, and Zambia. The image does not establish the specimen’s locality or quality grade.