mineral

Rainbow-coated amethyst (likely treated quartz)

Quartz, SiO₂; purple color from iron-related defects. The iridescent surface appears artificially coated, often with a titanium-based film.

AI-generated identification · may be incorrect

Amethyst is Mohs 7, vitreous, and hexagonal; purple quartz beneath the coating. The rainbow sheen is a surface treatment, not a natural crystal property.

Identified October 12, 2026More mineral →

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Physical properties

Amethyst is Mohs 7, vitreous, and hexagonal; purple quartz beneath the coating. The rainbow sheen is a surface treatment, not a natural crystal property.

Formation & geological history

Quartz forms in silica-rich hydrothermal veins and cavities, commonly in volcanic rocks. The pictured pieces appear split or shaped and coated after mining; the specimen’s geological age cannot be determined from the image.

Uses & applications

Primarily sold as a decorative or collecting specimen; untreated amethyst is also used in jewelry.

Geological facts

Natural amethyst gets its purple color from trace iron and irradiation; coatings can produce vivid iridescence that may wear or flake.

Field identification & locations

Purple color and quartz-like appearance suggest amethyst, but the bright rainbow glitter indicates artificial coating. Common sources of amethyst include Brazil and Uruguay; exact provenance is not identifiable here.