New minerals discovered in the world's largest rare earth deposit

Chinese scientists have discovered two new niobium-rich minerals in the Bayan Obo mine, which is the world's largest rare earth deposit and the third-largest niobium deposit, located in North China's Inner Mongolia autonomous region.

Yang Zhanfeng, secretary-general of the Chinese Society of Rare Earths and senior engineer at the Baotou Research Institute of Rare Earths, said niobium boasts a high melting point, corrosion resistance and superconductivity, making it highly irreplaceable in specialty steel, superconducting materials, aerospace, and other fields.

"The two newly discovered minerals are both characterized by high niobium content," he said. "They not only increase the variety of niobium-bearing minerals available for mineral processing and metallurgy in Bayan Obo, but also provide a new mineralogical perspective and key research material for understanding the enrichment mechanism, occurrence state and mineralization process of niobium."

One of the new minerals is roughly translated as Zuolin niobite. It was found in ore-bearing dolomite in the Bayan Obo deposit. With a density of 5.538 grams per cubic centimeter, it is a new metal oxide mineral composed mainly of barium, strontium and niobium, containing up to 52.9 percent niobium oxide.

The other new mineral is roughly translated as Hongrui. It has a density of 4.453 grams per cubic centimeter and is an oxide mineral primarily composed of magnesium, iron, and niobium, with a niobium oxide content of 32.8 percent.

The two new minerals were jointly discovered by a research team from the Institute of Geology and Geophysics of the Chinese Academy of Sciences, Jiangxi Institute of Applied Science and Technology, and the Baotou Research Institute of Rare Earths, Yang said.

The Bayan Obo deposit is not only the world's largest rare earth deposit and the third-largest niobium deposit, but also a treasury for mineralogical research, hosting more than 200 known mineral species to date.