mineral

Black polished stone or mineral fragment

Unidentified opaque dark mineral; possibilities include black tourmaline (schorl), obsidian, or hematite

AI-generated identification · may be incorrect

Appears as a small, highly polished, opaque black-blue piece with vitreous to resinous luster; hardness cannot be determined reliably from the blurred image. Crystal structure, cleavage, and specific gravity are undetermined.

Identified September 16, 2026More mineral →

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At a glance

Common name: Black polished stone or mineral fragment
Scientific name: Unidentified opaque dark mineral; possibilities include black tourmaline (schorl), obsidian, or hematite
Category: mineral
Identified: September 16, 2026
Method: Standard

AI Estimated Value

Approximately $1-$15 for a small common polished fragment; identified gem-quality material may range from $20-$100 or more.

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

Likely a polished or tumbled geological material, but the image lacks enough detail to identify its composition, formation process, or geological age.

Uses & applications

Small polished specimens may be used in jewelry, cabochons, carvings, or mineral collections; value depends heavily on confirmed identity, size, and finish.

Geological facts

Black tourmaline commonly shows elongated striated crystals, obsidian has glassy conchoidal fracture, and hematite is unusually dense with a reddish-brown streak.

Field identification & locations

Use a sharper close-up plus tests for streak, hardness, magnetism, density, and translucency. A white streak test and side-view inspection would help distinguish hematite, obsidian, and tourmaline.