mineral

Amethyst (rough quartz crystal)

Amethyst, purple variety of quartz (SiO₂)

AI-generated identification · may be incorrect

Mohs hardness 7; translucent lavender-to-purple areas with a vitreous luster and uneven fracture. Trigonal crystal structure; the pictured rough piece shows no obvious well-formed crystal points.

Identified October 15, 2026More mineral →

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Physical properties

Mohs hardness 7; translucent lavender-to-purple areas with a vitreous luster and uneven fracture. Trigonal crystal structure; the pictured rough piece shows no obvious well-formed crystal points.

Formation & geological history

Forms in silica-rich fluids within cavities and veins, where trace iron and natural radiation produce its purple color. Amethyst deposits range from ancient to relatively young and commonly occur in volcanic rocks.

Uses & applications

Used for jewelry, carvings, decorative objects, and mineral collections.

Geological facts

Amethyst is quartz colored by iron-related defects; strong heating can turn some material yellow or orange, resembling citrine.

Field identification & locations

Look for purple zoning and quartz-like hardness; it occurs worldwide, notably in Brazil, Uruguay, Zambia, and parts of the United States. The image is consistent with rough amethyst, though a photo cannot confirm identity.