Rocksday

Pyrolusite

Manganese dioxide, usually black and sooty; it leaves black marks on fingers.

Pyrolusite specimen
Photo: Unknown authorUnknown author, Public domain, via Wikimedia Commons

How to identify pyrolusite

  • Sooty black masses that dirty your fingers.
  • Black streak.
  • Fern-like black 'dendrites' on rock surfaces.

Often confused with

Where it's found

  • Germany
  • Brazil
  • Morocco
  • South Africa

Uses

Manganese for steel, and batteries.

Rock tumbling

Not suitable for tumbling.

Did you know?

Fern-like black 'fossils' on rock faces are usually manganese oxide dendrites, not plants.

Think you could spot it from a blurry close-up?

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