What to know about the U.S.-Ukraine minerals deal, from the type of rare earths to deposits

The joint economic investment deal announced Wednesday that gives the U.S. access to Ukrainian minerals may provide Ukraine with more support for its defense against Russia. But it also comes at a key moment for the American economy amid its growing trade war with China, a major producer of rare earths and other critical minerals. 

The new deal was described by Yulia Svyrydenko, Ukraine's economic development minister, as an equal partnership between the U.S. and Ukraine that includes development of mineral, oil and gas projects. The U.S. will provide either direct financial assistance or new military assistance to Ukraine, which will contribute half of any royalties from future oil, gas and mineral licenses. 

The pact comes as America's access to rare earth minerals, which are key to manufacturing high-tech products like computer chips and military equipment, has diminished after China last month announced export restrictions on some of these minerals in retaliation for U.S. tariffs. Although Mr. Trump has suggested buying Greenland, which has rare earths and critical minerals as well as oil and natural gas, Ukraine may provide a more readily available source for these strategically vital natural resources, experts say.