Cesium
A soft alkali metal that defines the second: cesium atomic clocks underpin GPS and network timing.
Atomic clocks and precision timing that synchronize telecom and data networks.
The US is 100% import reliant; no world production data published.
Who calls it critical
Membership on each government list. “Strategic” marks a higher tier where the list has one; “group” means included as part of a group such as rare earths or PGMs.
Cesium: key questions
- Where is cesium mined or produced?
- Country-level production data for Cesium is limited or withheld in USGS statistics.
- Is cesium a critical mineral?
- Cesium appears on 3 of the 10 official lists we track (United States, Japan, Canada).
- Is cesium in short supply?
- Our supply status: Watch. The US is 100% import reliant; no world production data published.
- Why does cesium matter for AI infrastructure?
- Atomic clocks and precision timing that synchronize telecom and data networks.
Related minerals
ExplorerBismuth
WatchA heavy, non-toxic metal used in pharmaceuticals, low-melt solders and lead-free alloys. China refines ~88%.
Tungsten
TightThe densest common metal with the highest melting point — used for cutting tools, armor, and as the 'plugs' that connect chip transistors to wiring.
Magnesium
WatchThe lightest structural metal, used in aluminum alloys, die-cast parts and titanium production. China makes ~86% of the metal.