gemstone

Blue sapphire (likely synthetic or treated corundum)

Corundum, aluminum oxide (Al₂O₃), blue from iron and titanium impurities

AI-generated identification · may be incorrect

Mohs hardness 9; vivid blue, vitreous luster, trigonal crystal structure, no true cleavage, specific gravity about 4.0. The sharply faceted, unusually saturated stone may be synthetic or laboratory-treated.

Identified September 8, 2026More gemstone →

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At a glance

Common name: Blue sapphire (likely synthetic or treated corundum)
Scientific name: Corundum, aluminum oxide (Al₂O₃), blue from iron and titanium impurities
Category: gemstone
Identified: September 8, 2026
Method: Standard

AI Estimated Value

About $5–$50 if synthetic or heavily treated; roughly $100–$5,000+ for natural stones depending on color, clarity, size, and certification.

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 sapphire forms in aluminum-rich metamorphic rocks or basalt-related deposits, commonly millions to billions of years old; synthetic sapphire is manufactured by crystal-growth methods. This cut specimen’s origin cannot be confirmed visually.

Uses & applications

Used in jewelry and as a durable abrasive, watch crystal, optical window, and electronic substrate. Fine natural stones can be highly valuable, while synthetic material is inexpensive.

Geological facts

Sapphire is the non-red gem variety of corundum; chromium-rich corundum is ruby. Color, inclusions, and treatment strongly affect value.

Field identification & locations

Identify by exceptional hardness, strong blue color, high density, and lack of cleavage; verify with refractive index, spectroscopy, and inclusion examination. Major natural sources include Sri Lanka, Myanmar, Kashmir, Madagascar, and Australia.