mineral

Blue glassy mineral fragment, likely kyanite or blue corundum

Tentatively kyanite (Al₂SiO₅); visual identification is uncertain from the photograph

AI-generated identification · may be incorrect

Bright cobalt-blue, translucent to transparent fragment with vitreous luster and irregular cleavage/fracture. Kyanite hardness is 4.5–5 parallel to length and 6.5–7 across it; corundum would be much harder (Mohs 9).

Identified August 19, 2026More mineral →

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At a glance

Common name: Blue glassy mineral fragment, likely kyanite or blue corundum
Scientific name: Tentatively kyanite (Al₂SiO₅); visual identification is uncertain from the photograph
Category: mineral
Identified: August 19, 2026
Method: Standard

AI Estimated Value

About $1–$20 as an unidentified fragment; approximately $20–$150 for attractive gem-quality kyanite, while confirmed blue sapphire could range from $50 to thousands per carat.

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

If kyanite, it formed during regional metamorphism of aluminum-rich sediments, commonly in schist and gneiss, typically during Paleozoic–Precambrian mountain building. The fragment appears natural but may be cut or broken.

Uses & applications

Kyanite is used in refractory ceramics, kiln materials, and occasionally as a gemstone; blue corundum is valued as sapphire. Commercial value depends strongly on confirmed identity, transparency, color, and treatment.

Geological facts

The intense blue color is characteristic of gem-quality kyanite or sapphire, but the visible shape and lack of diagnostic crystal form prevent confident separation from blue glass or treated material.

Field identification & locations

Test hardness, specific gravity, and refractive index; kyanite commonly shows bladed crystals and strong directional hardness, while sapphire scratches glass readily and has much higher density. Common sources include Nepal, India, Kenya, Tanzania, Brazil, and Sri Lanka.