Apple taps recycled rare earth elements for iPhone parts - Reuters https://www.reuters.com/article/us-apple-rareearths-idUSKBN1W31JG

"Apple said it will use recycled rare earths in its “Taptic Engine,” a part that lets iPhones mimic a physical button click despite being a flat pane of glass. The part is about one-quarter of the rare earth elements inside the iPhone models."