Rocksday

Coltan

Columbite-tantalite ore, the source of niobium and tantalum used in electronics.

Coltan specimen
Photo: Robert M. Lavinsky, CC BY-SA 3.0, via Wikimedia Commons

How to identify coltan

  • Black, heavy, submetallic grains or plates.
  • Dark brown streak.
  • Found in granite pegmatites.

Often confused with

Where it's found

  • DR Congo
  • Rwanda
  • Western Australia
  • Brazil

Uses

Tantalum capacitors in phones and computers; niobium for steel.

Rock tumbling

Not suitable for tumbling.

Did you know?

Mining of coltan in eastern Congo has been linked to funding armed conflict.

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