Glittering Stones >> Olivine Earring

Olivine Earring

At the high temperatures and pressures found at depth within the Earth the olivine arrangement is no longer stable. Below depths of about 420 km olivine undergoes a phase transition to the sorosilicate wadslyite and at about 530 km depth wadslyite transforms into ring woodier which has the spinel structure. These phase transitions lead to a discontinuous increase in the thickness of the Earth's mantle that can be observed by seismic methods.