gemstone

Blue glass-like gemstone, likely synthetic spinel or glass

Uncertain; possibilities include synthetic cobalt-blue spinel (MgAl₂O₄) or cobalt-colored glass

AI-generated identification · may be incorrect

Bright saturated cobalt-blue, transparent, strongly polished, and faceted with a rounded polygonal outline. Apparent hardness is uncertain: synthetic spinel is about Mohs 8, while glass is about 5–5.5; no reliable cleavage or crystal structure can be determined from the image.

Identified September 14, 2026More gemstone →

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At a glance

Common name: Blue glass-like gemstone, likely synthetic spinel or glass
Scientific name: Uncertain; possibilities include synthetic cobalt-blue spinel (MgAl₂O₄) or cobalt-colored glass
Category: gemstone
Identified: September 14, 2026
Method: Standard

AI Estimated Value

About $1–$20 for blue glass or common synthetic spinel; potentially $50–$500+ if verified natural sapphire, depending heavily on weight, clarity, treatment, and quality.

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

The uniform color, very large size, and faceted cut suggest a manufactured specimen rather than a natural mineral. Synthetic spinel is laboratory-grown; cobalt-blue glass is melted and shaped, with no geological age.

Uses & applications

Synthetic spinel may be used as an inexpensive jewelry simulant; blue glass is mainly decorative. It is not suitable for identifying as natural sapphire without gemological testing.

Geological facts

Natural sapphire (corundum, Al₂O₃) is another possibility, but the vivid even blue and apparent glassy appearance make it less likely. Refractometer, specific-gravity, loupe, and UV tests are needed for discrimination.

Field identification & locations

At approximately 10.6°N, 61.1°W, a manufactured blue simulant is more plausible than a naturally occurring large faceted sapphire. Check for bubbles or swirl marks (glass), facet-edge wear (glass), and doubling/refractive behavior; do not scratch-test valuable material.