 Rare earths are used in renewable energy technologies, but their availability is declining due to Chinese government quotas and illegal mining operations, leading to increased prices. There are only a few operating mines worldwide, including biennial bio in China, mountain pass in the US, and Mount Weldon, Australia. The major contributor to the GHG footprint of rare earth processing is hydrochloric acid, followed by steam use and electricity. Life cycle-based water and energy consumption is significantly higher compared with other metals. This article was authored by Nozhad Haq, Anthony Hughes, Singh Lim, and others.