The concentrate was produced within the mill's existing infrastructure, using existing technologies, and originated from a sample of monazite sands from a North American source. The REEs recovered were high concentrations and high purity, and will now go to a separation plant and downstream processing facility.

"To the company's knowledge, this is the first REE concentrate produced from monazite sands at any significant quantity in North America in over 20 years," president Mark Chalmers said.

The next step for Energy Fuels is to process the three tonnes of additional samples of monazite sands it owns. It will process that in the coming two months, it confirmed, so that it may further refine its process for recovering REEs and uranium.

It will continue its negotiations to obtain more monazite sands to process on a commercial scale at White Mesa. It also has been in talks on the potential sale of mill-produced REE concentrate to a separation facility.

Chalmers called the production a major milestone for the company as well as for US rare earth element production.

"Our company literally accomplished REE production in months, because we utilized existing resources, infrastructure and technologies. Successful testing at scale also demonstrates the importance of the White Mesa mill in helping the US re-establish its domestic REE supply chain."

If Energy Fuels is able to secure adequate quantities of monazite sands, it is targeting early 2021 for production of commercial REE concentrate quantities.

In addition to White Mesa, the company also holds the Nichols Ranch in-situ recovery (ISR) project in Wyoming and the Alta Mesa ISR project in Texas. White Mesa is the only conventional uranium mill operating in the US today.