Glass artists who polish their works to a high shine with cerium oxide are getting hit with a hugh price increase from a shortage of the rare-earth element. China has reduced exports of cerium oxide and prices at one supplier have gone from $10 per pound eight months ago to $66 today. A mine in California that closed in 2002 after it couldn’t survive against the cheap pricing from China has now reopened to help with supply.  There are alternative techniques and materials for polishing, but cerium oxide is the fastest. From the environmental perspective, perhaps China does have some good interests behind the shortage as they say the reduction came from tighter controls on the damage caused by mass-extracting rare earths.