mineral
Tumbled dark stone, possibly hematite or polished basalt
Uncertain; likely hematite (Fe₂O₃) or a polished mafic rock
AI-generated identification · may be incorrectSmall, smoothly rounded and highly polished specimen with dark gray-brown color and strong reflective luster. Hardness is visually indeterminate: hematite is about 5–6.5 Mohs; basalt typically 5–6. No cleavage is visible.
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Physical properties
Small, smoothly rounded and highly polished specimen with dark gray-brown color and strong reflective luster. Hardness is visually indeterminate: hematite is about 5–6.5 Mohs; basalt typically 5–6. No cleavage is visible.
Formation & geological history
Could be a naturally occurring hematite-rich pebble or human-tumbled basalt; the image does not reveal texture, streak, density, or magnetism needed for confident identification. Hematite commonly forms in hydrothermal, sedimentary, and weathering environments.
Uses & applications
Tumbled hematite is used for inexpensive jewelry and collecting; basalt is mainly used as aggregate and building stone. Estimated value is about $1–$10 for a small common tumbled piece.
Geological facts
The bright highlight is primarily from polishing, not necessarily metallic crystal faces. Hematite leaves a distinctive red to reddish-brown streak on unglazed porcelain; basalt generally leaves little or no streak.
Field identification & locations
The specimen is clearly geological, but the photograph alone cannot distinguish hematite from basalt, magnetite, or another polished dark stone. Test streak, magnetism, and specific gravity; specimens from the 13.5°N, 77.5°E region could plausibly be transported dark igneous rocks or iron oxides.
