A Chinese flag flutters at the Chinese Ministry of Commerce building in Beijing, China June 4, 2025. REUTERS/Florence Lo

By Colleen Howe

BEIJING (Reuters) -Global manufacturers have raised the alarm on China's decision to curb exports of rare earths alloys, mixtures and magnets.

Here is an overview of rare earths and China's measures:

WHAT ARE THEY?

Rare earths are a group of 17 silvery-white elements. One of their most important uses is in making magnets that power motion for cars, cell phones, missiles and other electronics.

ARE THEY RARE?

While not rare in the sense of being uncommon, they tend to occur in small quantities or mixed with other minerals, making extraction difficult and costly.

WHICH COUNTRY IS THE BIGGEST PRODUCER?

China mines about 60% of the world's rare earths and makes 90% of rare earth magnets. It sets quotas on output, smelting, and separation, which are monitored as a barometer of global supply.

WHY DOES CHINA DOMINATE PRODUCTION?

One of the most difficult processing steps is separating individual rare earths from each other.

While U.S. scientists helped developed a process called solvent extraction in the 1950s, radioactive waste made it unpopular in the United States.

Spurred by the government, China has expanded the industry since the 1980s, spending the last 30 years mastering solvent extraction, while cheap labour and relatively lax environmental standards give it a cost advantage.

China has put bans on its technologies for separating rare earths as well as producing magnets.

New separation technologies are being developed but are not yet widely used.

WHAT CURBS HAS CHINA CLAMPED ON EXPORTS?

On April 4, China added seven of the 17 rare earths metals - such as samarium, gadolinium, terbium, dysprosium, lutetium, scandium and yttrium-related items - to a list of export controls two days after President Donald Trump's sweeping tariffs took U.S. trade barriers to their highest in a century.

Exporters have to apply for a licence that industry sources say can take two to three months or longer, and shipments have been halted at many Chinese ports as applications are processed.

On May 13, China agreed to remove recent non-tariff countermeasures issued after April 2, which includes the rare earth curbs, as part of a temporary tariff deal, U.S. trade representative Jamieson Greer said.

However, since then, Greer has said China was "slow-rolling" their removal, and Trump complained that China violated the deal.

WHAT HAS CHINA SAID ABOUT THE CURBS?

China has defended its export curbs as "non-discriminatory" and not targeted at any specific country. The foreign ministry told media on Friday that China was ready for talks on the issue with relevant nations.

WHAT IMPACT HAVE THE CURBS ALREADY HAD?

Global automakers have warned that the measures could cause production delays and widespread shutdowns because rare earths are employed in key components, such as automatic transmissions and power steering.

(Reporting by Colleen Howe; Editing by Clarence Fernandez)