The two rarest commercial rare earth elements — lutetium for PET scanners, thulium for portable X-ray sources and surgical lasers.
Lutetium: Lutetium is critical for modern PET scanning diagnostics and is emerging as a key material in next-generation medical treatments and batteries.
Thulium: Thulium's unique properties as a portable radiation source and surgical laser material make it strategically important for defense and medicine despite its rarity.
Lutetium: Lutetium is the heaviest and rarest of the stable rare earth elements. It is used in PET scan technology, specialized catalysts, and is being investigated for next-generation solid-state batteries. Thulium: Thulium is the rarest and most expensive of the rare earth elements used commercially. It is used in portable X-ray equipment, surgical lasers, and as a radiation source.
As tracked by Critical Minerals HQ, Lutetium is currently $620 USD/kg and Thulium is $3,200 USD/kg. The two minerals are quoted in different units (USD/kg vs USD/kg), so see the live price panels above for the most recent figures.
Neither is "better" in absolute terms — each is engineered for different end-uses. Lutetium is primarily used for: PET scanner detectors (lutetium oxyorthosilicate), Petroleum refining catalysts, Cancer treatment radiopharmaceuticals, Solid-state battery research. Thulium is primarily used for: Portable X-ray sources (thulium-170), Surgical lasers for ophthalmology, High-performance magnets, Radiation-hardened electronics. The right mineral depends on the application.
Lutetium and Thulium are quoted in different units (USD/kg vs USD/kg), so a direct numeric rarity comparison from spot price alone is indicative only. See the indexed 25-year chart on the live page for relative scarcity behavior.
Specific US import-reliance percentages are not in our on-file reference text for either Lutetium or Thulium. See the official USGS Mineral Commodity Summaries for the latest figures.
Lutetium top producers (USGS): China, United States, Australia. Thulium top producers: China, Australia, United States. The mineral whose first-listed producer accounts for a larger share of global output carries the greater supply-chain concentration risk.
Lutetium: Lutetium is critical for modern PET scanning diagnostics and is emerging as a key material in next-generation medical treatments and batteries. Thulium: Thulium's unique properties as a portable radiation source and surgical laser material make it strategically important for defense and medicine despite its rarity.