péridotite à grenat

OBS: Il s'agit d'une péridotite contenant de nombreux cristaux de grenat pyropes noyés dans de l'olivine verdâtre.

CONT: Garnet peridotite is a coarse-grained, ultra mafic igneous rock which forms at extreme depths within the [Earth's] upper mantle, over 40 km in depth. As such, the rock is composed of high pressure, high temperature forming minerals such as olivine which gives the rock an [overall] green colouration of varying shades.