Rare earths are a group of 17 metals used to make magnets that turn power into motion. So-called heavy rare earths are used to build fighter jets and other high-performance weaponry. The US produces very small amounts of heavy rare earths and is reliant on imports. Mines in Myanmar's Kachin region are major producers of heavy rare earths that are exported to China for processing. Senior Trump administration officials said the decision to lift some sanctions was unrelated to the general's letter.
