Komatiite

“Lava from a hotter Earth”

Igneous

Komatiite is an extremely rare ultramafic volcanic rock that erupted as superheated lava (above 1,600°C) during the Archean Eon, when Earth's mantle was significantly hotter than today. No komatiite lavas are known to have erupted in the last 2 billion years.

Composition

olivine, pyroxene, chromite, glass

Where Found

Komati River (South Africa — type locality), Abitibi Belt (Canada), Barberton Greenstone Belt

Mohs Hardness

6-7

Fun Fact

Komatiite displays a unique texture called 'spinifex' — long, blade-like olivine crystals that record the incredibly rapid cooling of extraordinarily hot lava.