Molybdenite

A soft, silvery molybdenum sulfide that forms flexible, greasy hexagonal flakes.

Molybdenite specimen — Photo: Didier Descouens, CC BY 3.0, via Wikimedia Commons

How to identify molybdenite

Bluish lead-gray flakes that feel greasy.
Soft enough to mark paper.
Greenish streak on a porcelain plate.

Often confused with

Graphite
Graphite is blacker, lighter, and leaves a black streak.
Compare side by side

Where it's found

Climax, Colorado
Quebec, Canada
Queensland, Australia

Uses

Molybdenum for steel, and MoS₂ dry lubricant.

Rock tumbling

Not suitable for tumbling.

Did you know?

Molybdenite and graphite were confused for centuries; both were called 'molybdaena'.

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