Terbium

Overview

Terbium is a silvery heavy rare-earth metal, element 65. It is one of the scarcer lanthanides: its average concentration in the Earth's crust is about 1.2 parts per million, compared with 39 ppm for lanthanum.¹²

Its most important use today is in high-performance permanent magnets. Sintered neodymium-iron-boron (NdFeB) magnets lose remanence and coercivity quickly as they heat up. Adding a heavy rare earth such as terbium or dysprosium raises the magnet's anisotropy field and intrinsic coercivity, which is why these elements are used in traction motors for hybrid and electric vehicles.³ The EU Critical Raw Materials Act notes that the best-performing permanent magnets contain dysprosium and terbium.⁴

Terbium is on the US 2025 List of Critical Minerals. The EU lists heavy rare earths as critical raw materials and classes rare-earth elements for magnets, including terbium, as strategic.⁵⁴

Where it comes from

Terbium is never mined on its own. It occurs with the other rare earths in minerals such as monazite, bastnaesite and euxenite and is separated by ion exchange and solvent extraction; the metal is made by reducing the anhydrous fluoride or chloride with calcium.¹ The US government records terbium as a potential by-product or co-product of other rare earths, iron ore and heavy mineral sands.⁵

Light-rare-earth ores such as bastnaesite contain little terbium. Ion-adsorption clay deposits in southern China, from which rare earths can be leached with weak acids, have been the world's main source of heavy rare earths.² Heavy rare earths are also elevated in ion-adsorption clays elsewhere: in 2025 a mine in Brazil produced mixed concentrates from ionic clays with elevated terbium and dysprosium.⁶

The US Geological Survey (USGS) does not publish terbium production by country. For all rare earths combined, world mine output was an estimated 390,000 t of rare-earth oxide (REO) in 2025, of which China produced about 270,000 t (about 69%).⁷ The chart below covers all rare earths, not terbium alone.

• China270,000 t · 69%
• United States51,000 t · 13%
• Australia29,000 t · 7%
• Burma22,000 t · 6%
• Thailand4,800 t · 1%
• India2,900 t · <1%
• Madagascar2,700 t · <1%
• Russia2,600 t · <1%
• Other countries4,310 t · 1%

Covers all rare earths combined, in rare-earth-oxide terms; USGS does not publish terbium output by country. World total is the USGS rounded figure; country figures sum to 389,310 t. USGS estimated Burma, Thailand and Madagascar from Chinese import data. Source: Mineral Commodity Summaries 2026: Rare Earths

Separation of heavy rare earths outside China is still small. In 2025 several companies produced small quantities of heavy-rare-earth compounds and metals in the United States, but none at sustained commercial scale. The US Department of War lent a Mountain Pass, California, producer 150 million US dollars to build a heavy-rare-earth separation plant, and an Australian producer announced plans for a facility in Malaysia to separate terbium, dysprosium and lutetium.⁶

What it is used for

• Permanent magnets. Terbium is added to NdFeB magnets that must work at elevated temperatures, such as vehicle traction motors. Patented manufacturing routes aim to cut the amount of dysprosium or terbium each magnet needs.³
• Phosphors. Terbium provides the green in the red-green-blue phosphors (with europium and yttrium) used in lamps, panels and televisions.²¹
• Magnetostrictive alloys. A terbium-dysprosium-iron alloy changes shape in a magnetic field and is used in devices such as flat-panel speakers.¹
• Other uses include dopants for solid-state devices, safer medical X-ray imaging, lasers and security inks on banknotes.¹

Grades and forms

Terbium is traded mainly as high-purity oxide, with metal, master alloys and terbium-containing magnets further down the chain. USGS tracks terbium oxide of at least 99.99% purity.⁶ The forms below match the product groups covered by China's export licensing.⁸

Trade and policy

The United States imports all of the terbium compounds and metals it uses, and shipping records show that all imports in 2021–24 came from China.⁶ This makes terbium one of the materials most exposed to Chinese export policy.

As of December 2025 the April 2025 licensing requirement for terbium remained in effect, although China had begun issuing general licences to selected exporters.⁶

In the EU, listed products such as MRI devices will need labels showing whether they contain NdFeB or other permanent magnets, and makers will have to publish the share of neodymium, dysprosium, praseodymium, terbium and other metals in those magnets that was recovered from post-consumer waste.⁴

This section is factual background, not legal or trade-compliance advice.

Recycling and substitution

Only small quantities of heavy rare earths are recovered from used permanent magnets.⁶ In 2025 the US Department of War supported two recyclers to recover rare earths, including terbium and dysprosium.⁶ The EU Critical Raw Materials Act names permanent magnets as a priority product for recycling.⁴

Substitutes for heavy rare earths exist for some uses but are generally less effective; light rare earths can replace heavy ones in several applications.⁶ In magnets, dysprosium and terbium are used as alternatives for the same purpose.³

Sources

1. Terbium: element information, properties and uses. Royal Society of Chemistry, accessed 2026-10-03. ↩ ↩² ↩³ ↩⁴ ↩⁵

2. The Rare-Earth Elements: Vital to Modern Technologies and Lifestyles (Fact Sheet 2014–3078). U.S. Geological Survey, accessed 2026-10-03. ↩ ↩² ↩³

3. US 9,468,972 B2: Method of making Nd-Fe-B sintered magnets with reduced dysprosium or terbium. GM Global Technology Operations LLC (via Google Patents), accessed 2026-10-03. ↩ ↩² ↩³

4. Regulation (EU) 2024/1252 (Critical Raw Materials Act). EUR-Lex, accessed 2026-10-03. ↩ ↩² ↩³ ↩⁴

5. Final 2025 List of Critical Minerals. Federal Register, accessed 2026-10-03. ↩ ↩²

6. Mineral Commodity Summaries 2026: Rare Earths (Heavy). U.S. Geological Survey, accessed 2026-10-03. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹

7. Mineral Commodity Summaries 2026: Rare Earths. U.S. Geological Survey, accessed 2026-10-03. ↩

8. Announcement No. 18 of 2025 on implementing export control on some medium and heavy rare earth related items. Ministry of Commerce of the People's Republic of China, accessed 2026-10-03. ↩ ↩²

9. China Suspends Export Controls on Certain Critical Minerals-Related Items. Pillsbury Winthrop Shaw Pittman, accessed 2026-10-03. ↩

10. China Temporarily Suspends Export Controls on Key Raw Materials Including Rare Earths, Lithium Batteries, and Diamond. CIRS Group, accessed 2026-10-03. ↩ ↩²

11. China issues first batch of streamlined rare earth export licences, source says. Reuters via Yahoo Finance, accessed 2026-10-03. ↩

12. China Imposes Escalated Export Controls on Dual-Use Items to Japan. Greenberg Traurig, accessed 2026-10-03. ↩