A few days ago I spotted an article on the web under the headline Your Prius' Deepest, Darkest Secret points out that many products which appear to to reduce ones environmental footprint actually contain relatively large quantities of rare earth elements, which have to be mined and refined — a dirty process at the best of times.
Neodymium magnets turn wind turbines. Cerium helps reduce tailpipe emissions. Yttrium can form phosphors that make light in LED displays and compact fluorescent lightbulbs. Hybrid and electric cars often contain as many as eight different rare earths ... Walk down the aisles of your local Best Buy and you'll be hard-pressed to find something that doesn't contain at least one of the rare earths, from smartphones to laptop batteries to flat-screen TVs. They're also crucial for defence technology—radar and sonar systems, tank engines, and the navigation systems in smart bombs.No surprise therefore that the demand for rare earths is sky-rocketing and mining is expanding accordingly. Mining and refining produce mountains of waste from rock spoil to harsh acids as well as consuming gargantuan quantities of energy. And mining companies don't have good track records at reducing and managing any of this.
Another side of the coin is that many of these elements are used in such small quantities that recovering them from old products and recycling them becomes equally as hard as the original refining.
As I pointed out here and as the article concludes: What good is green technology if it's based on minerals whose extraction is so, well, ungreen?