Image: Komatiite (fresh surface)
Komatiite (fresh surface) (10 cm x 6 cm). Ravensthorpe, Western Australia.
- Stuart Humphreys
- © Australian Museum
Komatiite is high in magnesium and crystallised at high temperatures. It commonly displays a spinifex (spiky grass) texture consisting of intergrown skeletal and bladed olivine and pyroxene crystals in a glassy groundmass. Most are Archaean in age.