gemstone

Amethyst (faceted gemstone)

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

AI-generated identification · may be incorrect

Transparent to translucent, vivid purple, vitreous luster, trigonal crystal structure, Mohs hardness 7, no distinct cleavage, specific gravity about 2.65. The large precision-cut stone and exceptionally uniform color suggest a faceted commercial gemstone, possibly synthetic or treated;…

Identified September 22, 2026More gemstone →

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At a glance

Common name: Amethyst (faceted gemstone)
Scientific name: Quartz, silicon dioxide (SiO₂), purple variety colored mainly by iron-related defects
Category: gemstone
Identified: September 22, 2026
Method: Standard

AI Estimated Value

About $10–$100 for common faceted stones; $100–$500+ for large, vivid, well-cut natural stones. Synthetic or heavily treated examples may be under $20.

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

Natural amethyst forms in silica-rich hydrothermal cavities, especially in volcanic rocks, with color developing through irradiation and iron impurities. Major deposits occur in Brazil, Uruguay, Zambia, and elsewhere; it is not a typical geological material around Mumbai (19.1°N, 72.9°E), where basalt and weathered coastal sediments are more plausible.

Uses & applications

Used in jewelry, ornamental objects, and mineral collecting. Clear, strongly colored natural stones are more valuable; heat-treated or synthetic material is common.

Geological facts

Amethyst is the purple member of the quartz family and is the February birthstone. Heating can turn it yellow-orange, producing citrine-like material.

Field identification & locations

Identify by hardness, glassy luster, purple zoning, and quartz-like inclusions; glass imitations may show bubbles and lower hardness. Confirm with refractive index (about 1.544–1.553) or gemological testing.