Pyrolusite

Introduction: Pyrolusite was once used as an additive in glass making to remove brown and green tints. It derives from the Greekwords  pyros, meaning 'fire' and louxo 'to wash'. It is found as minute, shiny black metallic crystals, or in solid layers.

Distribution: Common in the Kombat Mine and the Otjosondu manganese field.

Composition: Oxide

Crystal system: Tetragonal

Lustre: Dull, metallic

Streak: Black

Hardness: 2-6.5