About rare Earths

PRODUCTION OF RARE EARTH ELEMENTS

Rare earth elements (REEs) are generally extracted from either hard rock or ionic clay deposits, such as Serra Verde’s. Ionic clay deposits, which are predominantly found in China, are the most important source of heavy and critical light REEs and have several benefits over hard rock deposits.

Ionic deposits are easier and cheaper to mine as they are typically near surface, and do not require blasting or energy intensive crushing or milling processes. Hard rock deposits also generally have a higher environmental impact as they produce radioactive tailings that require long-term management. Furthermore, clay deposits generally produce a higher proportion of heavy and critical rare earth oxides and the concentrates they produce are much simpler to process than those originating from hard rock deposits – which require complex capital-intensive processing infrastructure.

About Rare Earth Elements

REEs are a group of fifteen periodic table elements (atomic numbers 57 to 71), and two other elements of similar properties, Yttrium and Scandium. REEs are subdivided into two groups; light rare earth elements (LREE), and heavy rare earth elements (HREE).

REEs are key components in many electrical devices and some are vital to the production of permanent magnets, which improve the efficiency of electric motors. Demand for heavy and magnetic rare earths is expected to grow by seven times by 2040 driven by renewable energy applications such as EVs and wind generation.

The International Energy Authority estimates that a single EV motor uses more than 1kg of REEs¹, while research by the European Commission found that 2 tons of REEs are required to build a 3 MW wind turbine². The rare earths produced by Serra Verde are considered critical raw materials in the US and EU.

Permanent magnets are generally made from an alloy of neodymium (Nd), dysprosium (Dy) (or terbium (Tb)), praseodymium (Pr), iron, and boron. The benefit of these magnets is that they are light and strong with a high resistance to de-magnetization. They can also be made in small sizes and various shapes. Magnets are one of the primary components in electric motors, and to ensure maximum efficiency the motor needs to be energy dense and small, particularly in EVs where it is vital to preserve and maximize battery life and range.

The production process for REEs is more complex than for other raw materials and, due to a lack of historic resource development, there is a risk of a major shortage that could delay the world’s transition away from fossil fuels. China currently accounts for approximately 91% of refined global rare earth production.

Sources

[1] https://www.iea.org/reports/the-role-of-critical-minerals-in-clean-energy-transitions/mineral-requirements-for-clean-energy-transitions

[2] https://www.sciencedirect.com/science/article/pii/S0301420717300077

Our Products & Markets

Serra Verde will produce a mineral concentrate containing high value REEs – particularly Nd and Pr (both of which are Light Rare Earths) and Dy and Tb (both of which are Heavy Rare Earths). These four REEs are expected to be most in demand as they are used together to manufacture the permanent magnets necessary for electric vehicles and wind turbines.

Nd, Pr, Dy and Tb constitute the vast majority of the value in the concentrate that Serra Verde will produce.  Most hard rock REE producers mine monazite or bastnaesite ores which are typically higher in light REEs.

Our concentrate product has already been widely tested and accepted by major customers with whom we have offtake agreements and we operate to ISO 9000 standards for quality management.

glossary

REE: Rare Earth Elements

HREE: Heavy Rare Earth Elements

LREE: Light Rare Earth Elements

NdFeB: Neodymium magnet is a permanent magnet made from an alloy of neodymium, iron, and boron. NdFeB are the strongest type of permanent magnet available commercially.

Important REEs and their uses:

  • Lanthanum(La) – used in high-end optical lenses and in lanthanum nickel-metal hydride (NiMH) rechargeable batteries
  • Cerium(Ce) – the 25th most abundant element in the Earth’s crust (so not rare at all), used in catalytic converters and the oxide as a polishing powder 
  • Praseodymium (Pr) – oxide is used as a catalyst in plastic manufacturing and is combined with zirconium oxide to produce a vivid yellow pigment used in ceramics
  • Neodymium(Nd) – used to make super-strong magnets; neodymium-iron-boron (NdFeB) magnets are used to make cell phones vibrate
  • Promethium(Pm) – used to make a phosphorescent pigment and to make the starter switch for fluorescent lamps
  • Samarium (Sm) – used in high strength magnets and to make servo-motors
  • Europium(Eu) – used to make phosphors, notably the reddish-orange color of screens and monitors
  • Gadolinium(Gd) – used in a reactor to control rods to control fission reaction and as a contrast agent to improve magnetic resonance imaging (MRI)