mineral

Small rough quartz-family crystal specimens, including likely amethyst and citrine

Quartz, silicon dioxide (SiO₂); purple specimen is likely amethyst, yellow specimen likely citrine or iron-stained quartz

AI-generated identification · may be incorrect

Hardness 7 Mohs; vitreous luster, translucent to transparent, hexagonal crystal structure, and indistinct cleavage with conchoidal fracture. Colors visible include purple, pale yellow, clear/white, and gray-green; exact identification is limited by the blurred image.

Identified August 15, 2026More mineral →

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At a glance

Common name: Small rough quartz-family crystal specimens, including likely amethyst and citrine
Scientific name: Quartz, silicon dioxide (SiO₂); purple specimen is likely amethyst, yellow specimen likely citrine or iron-stained quartz
Category: mineral
Identified: August 15, 2026
Method: Standard

AI Estimated Value

About $2–$20 for small common rough pieces; attractive crystals or verified uncommon minerals may sell for $20–$100+.

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

Formation & geological history

Quartz crystallizes from silica-rich hydrothermal fluids and igneous cavities, commonly in geodes and veins; amethyst color comes from irradiation plus iron impurities. These specimens may range from geologically ancient to relatively young depending on their host deposit.

Uses & applications

Used as gemstones, decorative mineral specimens, abrasives, and in quartz-based technology; these appear primarily suitable for collecting rather than high-end jewelry.

Geological facts

Amethyst is purple quartz, while natural citrine is yellow-to-orange quartz; much commercial citrine is heat-treated amethyst. A glass-scratch test should be avoided because it can damage specimens, though quartz commonly scratches ordinary glass.

Field identification & locations

Look for glassy luster, hardness, conchoidal fracture, and six-sided crystal faces; purple quartz is common in Brazil, Uruguay, Zambia, and Mexico, while yellow quartz occurs worldwide. The gray-green piece could be another mineral and needs a clearer image or testing.