# Mantle Transition Zone

Subducted Secrets: How Ancient Ocean Floors Forge Earth’s Most Precious Diamonds

A breakthrough study led by the University of Cape Town reveals that the world’s largest and rarest diamonds are formed from recycled oceanic crust subducted deep into the Earth's mantle. The research identifies specific isotopic signatures that link these 'CLIPPIR' diamonds to ancient seafloor processes and mantle upwelling.