gemstone

Unidentified polished dark gemstone cabochon

Possibly hematite, obsidian, jet, or dark agate; image insufficient for a definitive identification

AI-generated identification · may be incorrect

Small, highly polished, dark gray-black, opaque cabochon set in a gold-colored mount with a vitreous to metallic-looking surface. Hardness and crystal structure cannot be determined visually; hematite is Mohs 5–6.5, obsidian 5–5.5, jet 2.5–4, and agate 6.5–7.

Identified August 16, 2026More gemstone →

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At a glance

Common name: Unidentified polished dark gemstone cabochon
Scientific name: Possibly hematite, obsidian, jet, or dark agate; image insufficient for a definitive identification
Category: gemstone
Identified: August 16, 2026
Method: Standard

AI Estimated Value

Approximately $5–$75 as a common mounted cabochon; substantially more only if confirmed as a valuable gemstone or collectible antique.

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 geological origin depends on composition: hematite forms in iron-rich hydrothermal or sedimentary environments, obsidian from rapidly cooled volcanic lava, and agate from silica-filled cavities. No geological age can be assigned from the photograph.

Uses & applications

Likely used as jewelry or a decorative pendant; dark cabochons are commonly made from hematite, obsidian, agate, onyx, or jet.

Geological facts

The gold-colored setting and reflective surface may obscure diagnostic features, and it could also be an antique or synthetic jewelry stone rather than a natural specimen.

Field identification & locations

Field identification requires testing streak, hardness, magnetism, translucency, and specific gravity; a reddish-brown streak would support hematite, while conchoidal fracture supports obsidian. Common sources include Brazil, Mexico, the United States, India, and the United Kingdom, depending on material.