He is a Métis, that is, the son of a white father and Indian mother. He has dwelt long in cities where Europeans have conducted business, and speaks English and French very well; the other two chiefs are a Negro and an Indian: […]
Keep a book in your bag to avoid the temptation to doomscroll.
A man but young, / Yet old in judgment, theoric and practic / In all humanity
All rocks around us contain significant amounts of rare earth elements, but they become concentrated in these exotic magmas through slow crystallisation in Earth’s crust. This is usually not enough to make an ore deposit, which consists of millions of tonnes of rock made up of between 5 and 50% by weight of rare earth elements. A second step of concentration is required. In giant deposits such as Bayan Obo in Inner Mongolia, hot fluids loaded with carbonate appear to have undergone this extra concentration step. But exactly how has been a mystery.
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