Rare Earths in real life are required for many electronics and specialised machinery (e.g. EMRs, lasers) as well as battery technology. I included it with the intention to make it either a requirement or an accelerating resource for modern buildings and wonders (e.g. Solar Plants) and to include it in the Computer Industry corporation. It also ties in with the late game expansion that is also planned. I think everything that expands on the modern era is good for the game and there are few resources that come into play this late. Deposits are in China, Mongolia, India, Sri Lanka, Australia, Madagascar, Tanzania, South Africa, Congo, Brazil, USA, Ukraine, Kola peninsula, Sweden and Greenland.