Olivine—The Little Green Science Machine

In some ways, olivine has driven the evolution of the Solar System and likely beyond. As one of the earliest-crystallizing silicate minerals, olivine controls the initial chemical evolution of planet-wide magma oceans and individual lava flows alike. In solid aggregate form, it controls and records deformation of the mantle and smaller-scale intrusive complexes. The components of its crystal structure are mobile at high temperatures and their migration can be used to explore the timing of magmatic events. During chemical weathering, these olivine crystals capture carbon dioxide from the atmosphere as secondary minerals are formed. All of these processes take place not only on Earth, but also on other planetary bodies, making olivine ideally suited to shed light on both primordial planet-building processes and current-day volcanism and surface processes.