mineral

Amethyst (rough crystal fragment)

Quartz, silicon dioxide (SiO₂), purple variety colored mainly by iron-related impurities

AI-generated identification · may be incorrect

Mohs hardness 7; translucent violet to purple, with a vitreous luster and conchoidal fracture. It is trigonal (hexagonal crystal system), has no cleavage, and a specific gravity around 2.65.

Identified August 20, 2026More mineral →

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At a glance

Common name: Amethyst (rough crystal fragment)
Scientific name: Quartz, silicon dioxide (SiO₂), purple variety colored mainly by iron-related impurities
Category: mineral
Identified: August 20, 2026
Method: Standard

AI Estimated Value

About $2-$15 for a small rough fragment; attractive cabinet specimens or gem-quality material may range from $25 to several hundred dollars.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Mohs hardness 7; translucent violet to purple, with a vitreous luster and conchoidal fracture. It is trigonal (hexagonal crystal system), has no cleavage, and a specific gravity around 2.65.

Formation & geological history

Forms when iron-bearing quartz is irradiated within cavities of volcanic rocks, especially basaltic lava flows; many important deposits formed during the Mesozoic and younger periods. The image shows a small irregular fragment rather than a complete crystal.

Uses & applications

Used for jewelry, ornamental carvings, crystal specimens, and lapidary work; finely colored transparent material is cut as a gemstone.

Geological facts

Amethyst is the traditional February birthstone and was historically valued alongside other gemstones. Heating can turn it yellow-orange, producing citrine or ametrine-like material.

Field identification & locations

Identify it by purple color, glassy luster, hardness, and lack of cleavage; glass and fluorite are common look-alikes. Major sources include Brazil, Uruguay, Zambia, Bolivia, and Namibia.