gemstone

Likely polished dark gemstone cabochon

Indeterminate; possibly black chalcedony/agate, obsidian, or glass imitation

AI-generated identification · may be incorrect

Small oval cabochon set in a metal ring or holder; dark gray-black, vitreous to waxy luster with a pink reflection or inclusion. Hardness cannot be determined visually: chalcedony is about 6.5–7 Mohs, obsidian 5–5.5, and glass about 5–6.

Identified September 14, 2026More gemstone →

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At a glance

Common name: Likely polished dark gemstone cabochon
Scientific name: Indeterminate; possibly black chalcedony/agate, obsidian, or glass imitation
Category: gemstone
Identified: September 14, 2026
Method: Standard

AI Estimated Value

About $2–$20 as an unidentified set cabochon; roughly $10–$75 if verified as attractive natural chalcedony or obsidian. If it is glass, usually under $5.

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 image shows a human-polished specimen, not its natural matrix. If chalcedony, it formed as microcrystalline silica filling cavities in volcanic rock; if obsidian, it is rapidly cooled volcanic glass. Age and formation location cannot be established from the photograph.

Uses & applications

Likely used as jewelry or a decorative cabochon. Black chalcedony and obsidian are common ornamental materials; value is generally modest unless unusually fine or documented.

Geological facts

The apparent pink spot may be a reflected object, an inclusion, or surface decoration, so it is not diagnostic. The surrounding metal setting makes identification less reliable.

Field identification & locations

Test with a 10× loupe for curved glass-flow lines, bubbles, or uniform manufactured color; chalcedony commonly shows waxy texture and translucency at thin edges. A scratch, refractive-index, or specific-gravity test is needed for confidence. Such materials are plausible near Sabah, Malaysia, but the image alone cannot distinguish them.