gemstone

Blue gemstone, likely iolite or blue sapphire

Iolite (cordierite, Mg₂Al₄Si₅O₁₈) or corundum (sapphire, Al₂O₃)

AI-generated identification · may be incorrect

Faceted blue stone with vitreous luster and apparent inclusions; exact identification requires refractive-index, hardness, and specific-gravity testing. Iolite is Mohs 7–7.5 with distinct pleochroism; sapphire is Mohs 9 and typically more durable.

Identified August 16, 2026More gemstone →

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At a glance

Common name: Blue gemstone, likely iolite or blue sapphire
Scientific name: Iolite (cordierite, Mg₂Al₄Si₅O₁₈) or corundum (sapphire, Al₂O₃)
Category: gemstone
Identified: August 16, 2026
Method: Standard

AI Estimated Value

Approximately $20–$150 for common faceted iolite; $100–$10,000+ for natural sapphire depending on treatment, color, clarity, size, and origin.

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

Iolite forms in metamorphic rocks, while sapphire crystallizes in igneous or metamorphic environments; both are ancient natural minerals, commonly concentrated in placer deposits.

Uses & applications

Used primarily in jewelry; sapphire has substantially greater durability and commercial value than iolite. The surrounding objects appear to include additional jewelry gemstones or pearls.

Geological facts

Strong blue-violet pleochroism strongly supports iolite, whereas sapphire usually shows more consistent blue color. The photograph alone cannot reliably distinguish them or exclude treated glass/synthetic material.

Field identification & locations

Check for color change when rotated, loupe-visible inclusions, and scratches only through professional testing; do not use destructive tests on jewelry. Iolite commonly comes from India, Sri Lanka, Madagascar, and Brazil; sapphire from Sri Lanka, Myanmar, Madagascar, Australia, and Kashmir.