What to know about Ukraine's rare earth minerals, which the U.S. wants

The big picture: Ukraine's willingness, or lack thereof, to share its minerals and the revenue from their sale may determine whether or not the U.S. ends all support for the country, as its war with Russia nears the start of its fourth year.

What are rare earth minerals?

Context: Rare earths, as the U.S. Department of Energy explains, are a series of elements that are crucial to modern electronics, batteries and the like.

• The U.S. has them, but not nearly in the quantities of some other countries.
• The Pentagon has already spent hundreds of millions of dollars trying to establish a rare earths supply chain, with limited impact so far.
• Most of the world's supply and production is in China, which is increasingly cracking down on exports.

What rare earth minerals does Ukraine have?

By the numbers: Ukraine has about 5% of the world's total reserves of critical rare earths, per UN data.

Zoom out: Ukraine, according to its national Geological Survey, has largely untapped reserves of minerals like tantalum, beryllium and niobium.

• Those minerals have applications in everything from capacitors in electronic devices to the brakes on jet aircraft.
• In total, the Ukrainian government estimates it is sitting on more than 2.6 billion tons of reserves of these crucial minerals — and some observers estimate that stockpile could be worth up to $11.5 trillion.
• The country also has significant reserves of other critical minerals like titanium and lithium.

What does the U.S. want from Ukraine?

Zoom in: As NBC and others have reported, Treasury secretary Scott Bessent offered Ukrainian president Volodymyr Zelensky a deal earlier this month: Give the U.S. 50% ownership of Ukraine's rare earths in exchange for U.S. investment in Ukraine.

• The Ukrainian side rejected that offer, but talks continued behind the scenes even as Trump engaged Zelensky in a public war of words.
• A source with knowledge tells Axios several of Zelensky's aides have encouraged him to sign the updated proposal to avoid a further clash with Trump.

What to watch: Whether the sides will strike a new deal, which could be key to changing the direction of the U.S.-Russia talks on ending the war.