43.93% Niobium. Is that good?, page-4

Niobium Minerals & Production | TIC (tanb.org)
Production of raw materials.The primary mineral from which niobium is obtained is known as pyrochlore. The world's largest deposit is located in Araxa, Brazil and is owned by Companhia Brasileira de Metalurgia e Mineracao (CBMM). The reserves are enough to supply current world demand for about 500 years, about 460 million tonnes.
The mining of weathered ore, running between 2.5 and 3.0% Nb2O5, is conducted by simple open pit mining without the need for drilling and explosives.Mineracao Catalao, Aerial view of Catalao plant (Ruy George Fischer)
Another pyrochlore mine in Brazil is owned and operated by Anglo American Niobio Brasil and contains 18 million tonnes, based on a grade of 1.34% niobium oxide.
The third major deposit of pyrochlore being actively mined is the Niobec Mine in Quebec, Canada, owned by IAMGOLD Corp, with measured and indicated resources of 2.6 million tonnes, based on a grade of 0.41% Nb2O5.