
Diamonds reveal hidden chemistry deep inside Earth
Diamonds from South Africa’s Voorspoed mine have revealed the first natural evidence of nickel-rich metallic alloys forming deep in Earth’s mantle, between 280-470 km (174-292 miles). A new study reveals that these inclusions coexist with nickel-rich carbonates, capturing a rare snapshot of a “redox-freezing” reaction whereby oxidized melts infiltrate reduced mantle rock. The growing diamond…