Uraninite identification and geology

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Sources, scope & corrections

These authoritative resources support category-level nomenclature, terminology, identification methods, and safety. When a specimen-specific safety warning appears, the public-health source listed here directly supports that precaution. They are not line-by-line citations for every other property on this entry, and natural specimens vary.

Editorial owner

GeoMiner

Last updated

2026-03-30T14:37:51.240558+00:00

Review status

Published; not independently peer-reviewed

• IMA–CNMNC List of Mineral Names — International Mineralogical Association. Official mineral-name, nomenclature, and classification records.
• Mineral ID Key — Mineralogical Society of America. Physical-property identification methods, repeat-testing guidance, and limitations.
• Technologically Enhanced Naturally Occurring Radioactive Materials from Uranium Mining — U.S. Environmental Protection Agency. Official radiation-safety guidance for mineral collectors, including uranium- and thorium-bearing specimens.

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Common questions

What is Uraninite?

Uranium dioxide and the most important ore of uranium. Variety pitchblende is the massive form.

How can you identify Uraninite?

Compare several properties rather than relying on colour alone. This entry records colour: Black, brownish-black; lustre: Submetallic to pitchy; streak: Brownish-black; Mohs hardness: 5-6; cleavage: None; crystal system: Isometric Cubic; transparency: Opaque. Confirm an important identification with additional field tests or qualified laboratory work.

How does Uraninite form?

Forms in granitic pegmatites, hydrothermal veins, and as detrital grains in conglomerates.

Where is Uraninite commonly found?

Canada, Democratic Republic of Congo, Czech Republic, Australia; found in pegmatites and veins.

Is Uraninite safe to handle?

Minimize handling and time near this specimen. Keep it in a closed, clearly labelled container away from occupied areas; do not cut, grind, powder, streak, or carry it in a pocket. Seek local radiation-safety guidance for large specimens or collections. Avoid creating dust or using destructive tests on an unknown specimen, and follow site-specific safety procedures.

What is Uraninite commonly confused with?

Uraninite may be confused with Thorianite, Magnetite, Chromite. Compare multiple diagnostic properties because colour and surface appearance can overlap.