gemstone

Dark blue-gray mineral pebble, possibly sapphire (corundum)

Unconfirmed; if sapphire, corundum (Al₂O₃)

AI-generated identification · may be incorrect

Small, opaque-to-translucent dark blue-gray fragment with reflective, possibly fractured faces. A photo cannot establish hardness, crystal form, or identity; corundum has Mohs hardness 9 and a trigonal crystal structure.

Identified September 25, 2026More gemstone →

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Physical properties

Formation & geological history

The appearance alone is insufficient to determine formation or age. The reported Sri Lankan region is known for gem-bearing metamorphic rocks and alluvial deposits, including sapphire, but this specimen cannot be confirmed as sapphire visually.

Uses & applications

If verified as corundum, it may be cut as a gemstone or kept as a specimen; otherwise, no specific use can be assigned.

Geological facts

Sri Lanka is a major source of sapphires, but many dark pebbles and minerals can resemble rough corundum. Gemological testing is needed for a reliable identification.

Field identification & locations

Have a gemologist check refractive index, specific gravity, and hardness; avoid scratch-testing, which can damage a valuable specimen. The image does not show diagnostic crystal faces or features that distinguish sapphire from alternatives.