Why Rare Earths?
Rare earth elements (“REE”) are on the list of the 35 minerals considered critical to the economic and national security of the United States as first published by the U.S. Department of the Interior on May 18, 2018. REEs consist of the lanthanide series (lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium) as well as scandium and yttrium. REEs are classified as “light” and “heavy” based on atomic number. Light REEs (LREEs) are comprised of lanthanum through gadolinium (atomic numbers 57 through 64). Heavy REEs (HREEs) are comprised of terbium through lutetium (atomic numbers 65 through 71) and yttrium (atomic number 39), which has similar chemical and physical attributes to the HREEs. Neodymium and praseodymium are key critical materials in the manufacturing of magnets that have the highest magnetic strength among commercially available magnets and enable high energy density and high energy efficiency in diverse uses. Dysprosium and terbium are key critical materials often added to the magnet alloys to increase the operating temperature. HREEs tend to be less abundant and more expensive than LREEs.
Rare Earths I — Our Rare Earths I Properties are inserted within the Goiás Tin Province (PEG), which is developed within the geological province of the Goiás Magmatic Arc. The region is marked by numerous magmatic events that developed in an orchestrated manner by the tectonics of the time. The PEG is characterized by a zone with type A granitic intrusions rich in tin and rare earth elements.
These fertile granites are responsible for the formation of supergene deposits with exotic minerals such as fluocerite-Ce, ETR oxifluorides, bastnaesite, monazite, allanite, solid solutions of zircon-torite and xenotite-torite in addition to apatite, rich in rare earth elements (REE). The area has a history of Sn deposits in PEG, and its potential for REE was not explored until the last decade, after which the region’s potential for world-class deposits was understood.
Rare Earths II — Our Rare Earths II Properties are located in the São Francisco Intracratonic Polycyclic Basin. This structure holds relics of a well-developed Proterozoic carbonatic platform responsible for the accumulation of carbonatic to mixed sediments of the Sete Lagoas Formation. These are the sediments that outcrop inside our mineral rights.
These same sediments hold large deposits of sedimentary phosphates, which may contain significant volumes of rare earth elements. When these sediments are subjected to fracturing and percolation of hot fluids (hydrothermalism) these elements solubilize along with the phosphate and fluoride elements and are remobilized in cracks, fractures and other dissolution features, such as karst. It is in this scenario that the target REE deposits are formed.
