Carnotite

A bright canary-yellow, powdery uranium vanadate that stains sandstones of the Colorado Plateau.

Carnotite specimen — Photo: Ra'ike (see also: de:Benutzer:Ra'ike), CC BY-SA 3.0, via Wikimedia Commons

How to identify carnotite

Canary-yellow powdery coatings, often on fossil wood.
Radioactive.
Very soft.

Often confused with

Sulfur
Sulfur is crystalline and not radioactive.
Compare side by side

Where it's found

Uravan, Colorado
Utah
Western Australia

Uses

Uranium and vanadium ore.

Rock tumbling

Not suitable for tumbling. Radioactive.

Did you know?

Carnotite from Colorado and Utah supplied much of the world's radium in the early 1900s.

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