mineral

Tumbled dark pebble, likely hematite or magnetite

Hematite (Fe₂O₃) or magnetite (Fe₃O₄); identification is uncertain from the image alone

AI-generated identification · may be incorrect

Small rounded, polished black-gray specimen with metallic to submetallic luster. Hematite hardness 5–6.5, specific gravity ~5.3; magnetite hardness 5.5–6.5, specific gravity ~5.2 and is strongly magnetic.

Identified September 22, 2026More mineral →

Explore Tumbled dark pebble, likely hematite or magnetite in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

At a glance

Common name: Tumbled dark pebble, likely hematite or magnetite
Scientific name: Hematite (Fe₂O₃) or magnetite (Fe₃O₄); identification is uncertain from the image alone
Category: mineral
Identified: September 22, 2026
Method: Standard

AI Estimated Value

About $1–$10 for a small common tumbled specimen; attractive, strongly magnetic, or locality-labeled pieces may sell for $10–$30.

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

Iron oxides form in igneous, metamorphic, and hydrothermal environments, or as weathering/concentration deposits; their ages range from recent sediments to Precambrian formations. Tumbling has smoothed the natural fragment.

Uses & applications

Used as an iron ore, pigment, polishing abrasive, and collectible; hematite cabochons are used in inexpensive jewelry. Magnetite is also used in dense media and industrial applications.

Geological facts

A magnet strongly attracting it favors magnetite; a red-brown streak favors hematite, while magnetite produces a black streak. The photo cannot reliably distinguish either mineral from other dark polished stones.

Field identification & locations

Common sources include banded iron formations, volcanic rocks, hydrothermal veins, and placer gravels worldwide. Test streak on unglazed porcelain, magnetism, and density; avoid scratching valuable surfaces.