mineral

Amethyst (large crystal point)

Quartz, SiO₂; purple coloration from trace iron and irradiation

AI-generated identification · may be incorrect

Mohs hardness 7; translucent to transparent violet-purple with a vitreous luster and hexagonal crystal structure. The specimen has a naturally formed prismatic crystal form with visible surface wear; quartz has no true cleavage and breaks conchoidally.

Identified September 26, 2026More mineral →

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Physical properties

Formation & geological history

Amethyst forms when silica-rich fluids deposit quartz in volcanic cavities, commonly in basalt geodes. Its age varies by deposit, and cannot be determined from appearance alone.

Uses & applications

Used in jewelry, carvings, decor, and mineral collections; lower-grade material may be used as ornamental stone.

Geological facts

Amethyst is the purple variety of quartz; heating can turn some material yellow or green, though treatment should be disclosed.

Field identification & locations

Identify by its purple color, glassy luster, hardness, and hexagonal prism habit; common sources include Brazil, Uruguay, Zambia, and Madagascar. This appears to be a substantial crystal, but quality and value depend on color, clarity, damage, and size.