Researchers from theUniversity of Alberta in Canadahave discovered a mineral previously unknown to science in the center of a shiny diamond– and it could change what we know about Earth’s mantle.
Named Goldschmidtite in honor of the Godfather of modern geochemistry Victor Moritz Goldschmidt, the new mineral is documented in the journalAmerican Mineralogistthis week.
Only asingle tiny grain of the deep green mineral can found in the center of the diamond located in a bed of kimberlite rock in South Africa. Using a series of geological tests, PhD studentNicole Meyerand a team of experts worked out that the diamond was formed some 170 kilometers (105 miles) underground at a temperature of 1,190°C (2,174°F).
Just as this specimen appears to have been, most natural diamonds were “cooked up” billions ofyears ago in theEarth’s mantle. Since this new mineral is locked in the middle of a diamond, we can assume it was created in these baking depths too. However, when researchers exploredthe chemical signature of the mineral, they noticed it had a signature you wouldn’t expect to see if it was forged in Earth’s mantle.
A tiny sample of goldschmidtite in all it’s glory. Credit: Nicole Meyer
Earth’s mantleis vast– over 1,800 kilometers (1,120 miles) thick – and marks the chunk of silicate rock between the crust and the core. Scientists actually know surprisingly little about this huge part of our ρłɑɴet as it’s found dozens of kilometers below the Earth’s surface underneath its crust. As such, scientists rely on minerals to study the potential chemical processes and conditions that exist here.
Taking into account the composition of goldschmidtite, outunderstanding of Earth’s mantle may bea little off the mark.
“Goldschmidtite has high concentrations of niobium, potassium, and the rare earth elements lanthanum and cerium, whereas the rest of the mantle is dominated by other elements, such as magnesium and iron,” study co-author Nicole Meyer, a doctoral student at the University of Alberta, said in aȿτɑτємєɴτ.”For potassium and niobium to constitute a major proportion of this mineral, it must have formed under exceptional processes that concentrated these unusual elements.”
