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Cesium

55132.9054520CsCesium[Xe]6s1Alkali metal
A sample of cesium
Photo: Dnn87 Contact email: Dnn87 yahoo.dk · CC BY-SA 3.0

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Photo Dnn87 Contact email: Dnn87 yahoo.dk. “Cesium.jpg.” CC BY-SA 3.0. Wikimedia Commons. File page

Chemical details

State at room conditions
Solid
Melting point
302 K (28 °C)
Boiling point
944 K (671 °C)
Density
1.93 g/cm³
Common oxidation states
+1
Electronegativity (Pauling)
0.79
Atomic radius
343 pm
First ionization energy
3.894 eV
Discovered
1860

Source: U.S. National Library of Medicine, PubChem, Periodic Table of Elements (element Cesium) (current at retrieval)

On the USGS 2025 List of Critical Minerals. Figures: USGS Mineral Commodity Summaries 2026 (data release, public domain). Estimates are USGS's; check the USGS chapter for notes. Each panel names its source; full citations are in the methodology source register.

Net import reliance, 2025100%share of U.S. use met by imports (USGS)
U.S. imports, 2025$21.1Munder the main trade codes for this mineral (Census; can include other goods)
Policy and funding items0tracked for Cesium; 1 federal awards already made

Overview

The headline numbers: how much the U.S. depends on imports and how concentrated supply is.

How much does the U.S. import?

100%

of U.S. cesium use was met by imports in 2025 (USGS net import reliance).

Source: U.S. Geological Survey, Mineral Commodity Summaries 2026: Cesium (February 2026)

Did you know?

Cesium melts at 28.5 °C, just above room temperature, making it one of only five metals that are liquid at or near room temperature.

Checked against two independent sources. Verified 2026-10-26.
Sources: Wikipedia · Los Alamos National Laboratory periodic table (Wikipedia text is CC BY-SA)

Supply

Who produces it, where the reserves are, where U.S. imports come from, and how U.S. supply has moved.

Where U.S. imports come from

Choose a data set, then a view. A country keeps the same color in every chart on this page. Grey means other countries, or a country beyond the seven colors (always labeled). Hover or focus a mark for its value, or use the table view.

Census dollars
Flow of 2805.19 Alkali metals except sodium into the United StatesChina45% · $9.6MGermany42% · $8.9MFrance10% · $2.2MIndia1% · $125KUnited Kingdom0% · $92KKorea, South0% · $55KAll other countries1% · $137KUnited Statesimports
China45% · $9.6M
Germany42% · $8.9M
France10% · $2.2M
India1% · $125K
United Kingdom0% · $92K
Korea, South0% · $55K
All other countries1% · $137K
Share of 2805.19 Alkali metals except sodium by country45%China
  • China45% · $9.6M
  • Germany42% · $8.9M
  • France10% · $2.2M
  • India1% · $125K
  • United Kingdom0% · $92K
  • Korea, South0% · $55K
  • All other countries1% · $137K
Change in import shares, Calendar 2025 to Jan to Aug 2026Calendar 2025Jan to Aug 2026China 45%48% ChinaGermany 42%46% GermanyFrance 10%0% FranceIndia 1%1% IndiaUnited Kingdom 0%1% United KingdomKorea, South 0%2% Korea, SouthTurkey 0%3% Turkey
CountryU.S. imports, 2025Share of this chart
China45% · $9.6M45.5%
Germany42% · $8.9M42.2%
France10% · $2.2M10.4%
India1% · $125K0.6%
United Kingdom0% · $92K0.4%
Korea, South0% · $55K0.3%
All other countries1% · $137K0.6%

U.S. general imports (customs value) in calendar 2025 under HS 2805.19; countries beyond the top six are grouped. The code can include goods beyond this mineral. The Shift view compares each country's share of 2025 with its share of Jan to Aug 2026 (shares of each period's total).

Source: U.S. Census Bureau, International Trade API: U.S. imports by HS code and country (calendar 2025; Jan to Aug 2026) (data months 2025-12, 2026-08)

Trade and tariffs

Tariff codes and the countries behind U.S. imports and exports.

Trade codes and tariffs

HTS codeWhat it coversNormal rateColumn 2 rate
2805.19Alkali or alkaline-earth metals: OtherFree to 5.5%25%

Rates from the U.S. Harmonized Tariff Schedule (USITC, saved 2026-10-26). The normal rate is column 1 general; column 2 applies to countries without normal trade relations. A range means different products under the code have different rates. Section 232, Section 301, emergency tariffs and antidumping or countervailing duties are set in separate notices and are not shown. Look up any code at hts.usitc.gov. These are the main codes for this mineral, not a complete list.

Source: U.S. International Trade Commission, Harmonized Tariff Schedule of the United States, general and column 2 rates (edition current when saved)

U.S. trade by country

U.S. imports in 2025 by source country, code 2805.19

China45% · $9.6M
Germany42% · $8.9M
France10% · $2.2M
India1% · $125K
United Kingdom0% · $92K
Korea, South0% · $55K

U.S. exports in 2025 by destination, code 2805.19

United Kingdom33% · $11.7M
Belgium17% · $6.0M
Netherlands11% · $3.8M
China7% · $2.6M
Dominican Republic4% · $1.6M
Canada4% · $1.4M

2805.19 Alkali metals except sodium

Imports 2025$21.1 million
Exports 2025$35.7 million
Duty collected 2025$1.4 million
Imports Jan to Aug 2026$17.2 million

Top import sources China 45%, Germany 42%, France 10%

Top export destinations United Kingdom 33%, Belgium 17%, Netherlands 11%

U.S. Census Bureau International Trade API, saved 2026-10-26. Imports are general imports (customs value) and exports are total exports, in U.S. dollars. Duty collected is Census's calculated duty on imports for consumption. Figures cover every 10-digit product under the code, so they can include goods beyond this mineral, and the duty shown is not split into Section 232, Section 301 or antidumping duties. Bars show the largest code for each direction. Group rows such as the EU or OECD are left out so no country is counted twice.

Source: U.S. Census Bureau, International Trade API: U.S. imports and exports by HS code and country (calendar 2025, and January to Aug 2026) (data months 2025-12, 2026-08)

Value chain and risk

Where in the chain the bottlenecks sit, and what other governments and sources say about supply risk.

Value chain: where the bottlenecks are

Mining bottleneck

No cesium was mined in the United States in 2025, which was 100% net import reliant for cesium minerals. (no U.S. activity)

The source says
“In 2025, no cesium was mined domestically, and the United States was 100% net import reliant for cesium minerals.”

Source: USGS Mineral Commodity Summaries 2026, Cesium (PDF page 68) (2026-02)

Ore processing and primary recovery

USGS has had no reliable data on the source of U.S. cesium ore imports since 1988; one Canadian company reported intermittent cesium production at the Tanco Mine in 2025. (U.S. role not stated)

The source says
“No reliable data have been available to determine the source of cesium ore imported by the United States since 1988.”
“During 2025, one company in Canada reported intermittent cesium production and processing from mined ore and stockpiles at the Tanco Mine.”

Source: USGS Mineral Commodity Summaries 2026, Cesium (PDF page 68) (2026-02)

Refining and separation

No sourced data yet.

Metal, alloy and chemical

China and Germany were estimated to be the sources of U.S. cesium chemicals. (no U.S. activity)

The source says
“Based on recent import data, it was estimated that China and Germany were sources of cesium chemicals.”

Source: USGS Mineral Commodity Summaries 2026, Cesium (PDF page 68) (2026-02)

Components and end use

Cesium carbonate and hydroxide are the leading cesium products consumed globally. (U.S. role not stated)

The source says
“cesium carbonate and hydroxide are the leading cesium products consumed globally”

Source: USGS Mineral Commodity Summaries 2026, Cesium (PDF page 68) (2026-02)

Recycling

Cesium formate drilling brines are returned and reprocessed, recovering nearly 85% of the brines. (partly U.S.)

The source says
“Cesium formate brines are recycled, recovering nearly 85% of the brines for recycling to be reprocessed for further use.”

Source: USGS Mineral Commodity Summaries 2026, Cesium (PDF page 68) (2026-02)

Pilot. Summaries are ours, from official pages; each quoted passage is checked against the saved page. “Bottleneck” (orange dot) is shown only where the quote shows one country dominating the stage or the United States relying on imports for it. “No sourced data yet” means we have not found a source, not that the stage is unproblematic.

Policy and funding

Federal items we track for this mineral, each linked to its original.

Federal awards already made

Geologic mapping, geochemistry, and geochronology in the quetico subprovince andadjacent boundary zones
Regents of the University of Minnesota · Department of the Interior · $318.5K obligated · started 2026-03-01
Source: usaspending.gov, retrieved 2026-10-29

The 1 largest of 1 AI-tagged awards from USAspending (last 12 months, found by keyword; some are only loosely about this mineral). See all awards for Cesium.

Source: U.S. Department of the Treasury, Bureau of the Fiscal Service, USAspending.gov: spending by award (contracts and grants, last 12 months) (award start dates per item)

Data tables

The USGS figures behind the charts. Click a column heading to sort.

Cesium: USGS tables

United States

MeasureUnit2025
The United States was 100% net import reliant for its cesium needspercent100
1?gram ampoules of 99.8% (metal basis) cesiumdollars per gram104
1?gram ampoules of 99.9% (metal basis) cesiumdollars per gram132
50 grams of 99.9% (metal basis) cesium acetatedollars per 50 grams161
50 grams of 99.9% (metal basis) cesium bromidedollars per 50 grams111
50 grams of 99.9% (metal basis) cesium carbonatedollars per 50 grams146.4
50 grams of 99.9% (metal basis) cesium chloridedollars per 50 grams166
50 grams of 99.9% (metal basis) cesium iodidedollars per 50 grams185.8
cesium-plasma standard solution (10,000 micrograms per milliliter) , 100 millilitersdollars per 100 mililiters155
25 grams of 98% (metal basis) cesium formatedollars per 25 grams56.1

World reserves

USGS note: Australia, Canada, China, and Namibia were estimated to have reserves totaling less than 200,000 tons. Other countries: <200,000 tons.

Source: U.S. Geological Survey, Mineral Commodity Summaries 2026: Cesium (February 2026)