Rubidium: Extraction
Why rubidium has always been someone else's by-product
Why rubidium has always been someone else's by-product What this tab covers How it is mined, drilled or grown, and processed into a tradeable form: the main methods compared, their unit economics, by-products, and the companies that do this work globally and in India.Rubidium is not a major constituent of any mineral. It sits in zoned pegmatites, mainly in lepidolite (up to 3.5% rubidium oxide) and pollucite (up to 1.5%). It has always been a by-product, first of cesium mining from pollucite and then of lithium mining from lepidolite. Concentrate is refined chemically into salts. Minor amounts occur in brines in Chile and China and in evaporites in the United States, France and Germany. USGS says extraction and concentration are mostly too costly.
Rubidium is not a major constituent of any mineral, so it is only ever a by-product. It is recovered when pollucite is processed for cesium or lepidolite for lithium. All known rubidium ore mining has stopped: Namibia ceased in the early 2000s, Bikita's pollucite ran out in 2018 and Sinclair finished in 2019. In 2025 refiners in China and Germany worked from stockpiles. New supply depends on lithium mica and spodumene projects adding recovery, and on new extraction methods being piloted in Australia.
Methods compared
| Method | Share of supply | Typical scale | Recovery / efficiency | By-products | Unit cost |
|---|---|---|---|---|---|
| By-product of pollucite (cesium) processing | a main historical source; current share not published | pollucite up to 1.5% Rb2O | not published | cesium (main product) | not published |
| By-product of lepidolite (lithium) processing | potentially the largest future source; not published | lepidolite up to 3.5% Rb2O; Namibia project resource 23,000 t Rb (JORC measured and indicated) | not published | lithium (main), cesium, potassium | not published |
| Stockpile drawdown | most 2025 supply (USGS) | not published | not published | cesium | not published |
| New direct extraction from rubidium-bearing rock (pilot) | none yet | 3.6 Mt inferred resource containing about 7,900 t Rb2O | 97% in initial testing | not published | not published |
How each method works
By-product of pollucite (cesium) processingWhen pollucite is digested in acid to make cesium salts, rubidium follows cesium chemically and is separated by fractional crystallisation or solvent extraction. Output is small and tied to cesium processing.
Uses existing cesium circuits, but pollucite mines are depleted.
USGS MCS 2026, Rubidium By-product of lepidolite (lithium) processingLepidolite is roasted or leached to recover lithium, and rubidium and cesium can be captured from the liquors. China's lithium-mica industry and projects in Namibia, Canada and the US could supply rubidium this way.
Large potential, but projects stall when lithium prices fall.
USGS MCS 2026, Rubidium Stockpile drawdownOre and concentrate stockpiled at former mines are shipped to refiners in China and Germany. This was the main supply route in 2025 because no ore was mined.
Immediate supply, but finite.
USGS MCS 2026, Rubidium New direct extraction from rubidium-bearing rock (pilot)At Mount Edon in Western Australia, initial tests of a rubidium extraction technology gave 97% recovery. The company planned to fund a scaled-up pilot plant in 2026.
Could create primary supply; unproven at scale.
USGS MCS 2026, Rubidium Unit economics are indicative ranges from the sources named; costs vary widely by deposit, region and year.By-product supply
Rubidium is a by-product of cesium (pollucite) and lithium (lepidolite) processing and is mined in smaller quantities than cesium, so it is no more available (USGS). No rubidium ore was mined in 2025. Supply cannot respond to rubidium prices; it waits on cesium or lithium projects, and USGS warns commercial ore stockpiles may be depleted in the near future.
Who does it: global
| Company | Country | Activity | Volume | Year | Source |
|---|---|---|---|---|---|
| Sinomine Resource Group Rubidium tonnage not published; combined cesium and rubidium salts revenue RMB 708 million in H1 2025, up 50.43%. | China | cesium and rubidium salts from Tanco and Bikita material | not published | H1 2025 | Asian Metal (25 Aug 2025) |
| Everest Metals (Mount Edon) Pilot stage; 97% recovery in initial tests. | Australia | rubidium extraction pilot project, Western Australia | 7,900 t Rb2O contained in inferred resource (not production) | 2025 | USGS MCS 2026 |
| Lepidico (Karibib project) Under administration from end-2024; new owner seeking financing in 2025. | Namibia | lepidolite lithium project with rubidium and cesium by-products | 23,000 t Rb in measured and indicated resource (not production) | 2025 | USGS MCS 2026 |
Who does it: India
India has no rubidium production, reserves or refining. Small quantities of compounds are imported for research, electronics and medical uses. Rubidium is not on India's 2023 critical list.