Encourage/Discourage notification letters were released and the Full Application NOFO was posted October 30, 2025.
Rare earth elements (REEs) and critical minerals are essential for modern energy technologies. REEs are key to high-performance magnets and motors, superconductors, and catalysts—critical components to energy production, transmission, and conversion systems necessary for U.S. energy security. Affordable and secure domestic critical mineral supply chains will advance future energy competitiveness. The U.S. possesses significant domestic resources of REEs and other critical minerals but operates only one productive REE mine.
The ROCKS program seeks fundamentally disruptive technologies to transform the ore deposit characterization process. The program will pursue technology that targets order-of-magnitude improvements in characterization with a primary focus on drilling, sensing, and analysis. These advances will shorten the timeline for feasibility assessments of REE and critical mineral deposits, leading to increased access to these resources. In addition, advances in sensing can aid assessment of currently untapped resources, such as seafloor mineral deposits.
By facilitating mine development and increased access to domestic mineral resources, the program furthers ARPA-E’s statutory goals to improve the energy security of the U.S., ensure resilient and reliable supply chains for energy-relevant materials, and maintain U.S. technological leadership in critical mineral resource development.
The ROCKS program seeks technologies that improve the characterization of critical mineral resources, with an emphasis on REEs. Technologies of interest are grouped into three main categories: (1) drilling technology to increase penetration rates and core recovery; (2) sensing and analysis technologies to provide higher-resolution mineralogical and geochemical information, in situ or at a distance; and (3) other unique concepts that disrupt the current state of resource characterization for hard rock settings as well as REE-enriched clays, placer deposits, and seafloor resources.