A Ph.D. student at the University of Alberta has found a new and extraordinary mineral in a South African mine in a diamond.
The mineral which is named Goldschmidtite in honor of Victor Moritz Goldschmidt, the founder of contemporary geochemistry, has a unique chemical signature from Earth’s mantle for a mineral, stated Nicole Meyer, a Diamond Exploration Research and Training School graduate student.
Goldschmidtite has elevated levels of niobium, potassium and rare earth elements lanthanum and cerium, while the remainder of the mantle is dominated by other components, such as magnesium and iron, remarked Meyer. For potassium and niobium to constitute a significant percentage of this mineral, it must have developed under extraordinary procedures that have focused on these different components. The researchers estimate that the diamond containing the Goldschmidtite was formed about 170 kilometers beneath the surface of the Earth in temperatures that were almost 1,200 C.
As it is challenging for workers to drill down through the Earth’s crust to reach the mantle, scientists rely on tiny mineral inclusions within the diamonds to get to know more about the Earth’s chemistry deep within the surface.
“The discovery gives us a picture of fluid methods that affect the deep roots of continents during diamond formation,” stated Meyer’s co-supervisor, Graham Pearson, who added there had been numerous attempts to name new minerals after Goldschmidt, but previous ones have been undermined. “This one is here to stay.”
“One person does not do the work that goes into finding a new mineral,” replied Meyer, who is also studying under the supervision of Thomas Stachel, professor, and Canada Research in Diamonds. “It has been an interdisciplinary collaboration with mineralogist Andrew Locock, crystallographers from Northwestern University, my advisers Thomas and Graham, and technicians.”
The study, “Goldschmidtite, (K, REE, Sr)(Nb, Cr)O3: a New Perovskite Supergroup Mineral Found in Diamond from Koffiefontein, South Africa,” was published in American Mineralogist.