On August 19, Energy Fuels announced that terbium oxide produced at its White Mesa Mill in Utah has received commercial-production certification from a major Japanese permanent magnet manufacturer. In March, the company had said a 99.9% pure prototype made from US-sourced monazite met the specifications of global magnet makers. This latest announcement differs in that the customer itself has now confirmed the material can be used in commercial permanent magnet production and that no further certification or verification is required.
The certification means the material has cleared one gate on its way into the customer's production process. However, it is not an announcement of sustained mass production or a sales contract. There remains a significant gap between meeting specifications in a prototype and having commercial-scale facilities actually up and running domestically.
Certified for use in the customer's process
What Energy Fuels disclosed is that one of the largest permanent magnet manufacturers outside China has certified its terbium oxide. The manufacturer determined that the material meets specifications and approved its use in commercial rare earth permanent magnet (REPM) production. No additional certification or verification was said to be needed.
In its March 25 announcement, the company had presented a 1 kg sample produced using its existing pilot circuit, describing it as 99.9% pure and meeting the specifications of magnet makers worldwide. There is a difference between a company stating that its material meets specifications and having a specific customer accept it for use in a commercial process. This latest development closes part of that gap.
At the same time, the name of the certifying Japanese manufacturer has not been disclosed. Test items, the number of lots tested, and measured performance data as magnets remain undisclosed. Purchase volumes, pricing, and the duration of any supply agreement have also not been made public, so the certification cannot be equated with an order or the start of commercial shipments.
An element added to NdFeB magnets used at high temperatures
Energy Fuels explains that terbium is used to enhance the heat resistance and performance of neodymium-iron-boron (NdFeB) permanent magnets. Cited applications include automobiles, advanced electronics, and robotics, with aerospace and defense also mentioned as examples. The certified material is an oxide, and what has been confirmed is that a magnet manufacturer judged it usable within its own manufacturing process.
Given the concentration of supply sources, the certification also serves as a step toward diversifying procurement, in addition to evaluating performance. According to the USGS, no company in the United States produced heavy rare earth compounds or metals at sustained commercial scale in 2025. Net import reliance relative to apparent consumption stood at 100%, and shipment records show China accounted for 100% of US imports of terbium compounds and metals from 2021 through 2024.
In April 2025, China tightened export controls on metals including terbium and dysprosium, with the same measures also covering oxides, alloys, and compounds. Additional measures added in October were suspended for one year in November of that year, but as of December 2025—the period covered by USGS data—the April measures remained in effect. Having US-produced material pass a customer's certification is a necessary condition for expanding supply options. However, it does not yet prove that supply volumes can actually be increased.
From a 1 kg/week pilot to a design capacity of up to 20 tons
As of March, Energy Fuels said its existing pilot circuit was expected to produce approximately 1 kg per week of terbium oxide—roughly 52 kg on a simple annualized basis. In the heavy rare earth expansion whose construction start was announced on July 29, the company designed for maximum annual production capacity of approximately 20 tons of terbium oxide and 120 tons of dysprosium oxide.
Twenty tons equals 20,000 kg, or about 385 times the simple annualized figure based on the pilot's weekly output estimate. However, this figure compares the pilot's operating rate with the commercial facility's maximum design capacity—it is not a forecast of actual annual production. Feedstock composition and recovery rates will determine actual output, which will also be affected by market conditions, permitting, and the pace of facility ramp-up.
The Tb/Dy circuit is scheduled for completion by the end of 2027, with commissioning planned for the fourth quarter of 2027, conditional on factors such as market demand. Certification was obtained ahead of this planned facility buildout. Even with the customer's determination that the material is usable, it remains a separate matter to confirm whether the facility can repeatedly deliver the volume and quality specified in its design.
A high price does not guarantee sales
In its August 19 announcement, Energy Fuels cited a Benchmark Mineral Intelligence CIF Europe index price for terbium oxide of approximately $5,500,000 per ton. This is a market price indicator presented through the company's own announcement, not an independently obtained spot price. It is difficult to gauge the profitability of commercial production based on this figure alone.
According to the USGS, the average 2025 price for terbium oxide of 99.99% purity or higher was $1,010 per kg, or $1,010,000 per ton. The two figures differ in timing, region, and transaction terms. As a result, the $5,500,000 index figure cannot simply be compared as a multiple of the 2025 average to calculate price increases or project future sales.
That said, the fact that this is a high-value material based on price indicators reinforces why reproducibility of quality becomes critical when scaling to commercial volumes. Meeting a magnet manufacturer's specifications once is not sufficient grounds for a decision on sustained supply. The yield and actual production volumes that Energy Fuels has not disclosed remain a gap in assessing the business's viability following certification.
What remains to be demonstrated after certification
What this certification confirms is that terbium oxide derived from the White Mesa Mill has been judged usable in commercial REPM production by at least the certifying customer. The next step is whether the Tb/Dy circuit under construction proceeds according to its planned completion by the end of 2027. Commissioning, planned for the fourth quarter of 2027 conditional on factors such as market demand, will need to be followed by confirmation of how far actual production volumes can scale.
Securing feedstock, maintaining recovery rates, and consistently delivering the same quality will also be necessary. Beyond that, it will be essential to confirm how much customers—including the manufacturer that issued this certification—actually order, and when commercial shipments begin. Whether sales contracts and shipment records not yet disclosed appear in future updates will be the material that determines whether US heavy rare earth supply can actually be supplemented.