China produces the vast majority of two particularly important rare earths, dysprosium (99%) and neodymium (95%).

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Sure, you could buy 500 kg of neodymium, or 50 kg of dysprosium.

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Promethium is necessary for guided weapons and Dysprosium is employed in sonar systems.

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By alloying neodymium with dysprosium, magnets are created that more readily maintain their magnetism at the high temperatures of hybrid car engines.

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Not all 17 are particularly rare, but dysprosium, critical for magnets, is.

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Prices for Chinese dysprosium have more than tripled since May.

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The property is rich in neodymium, dysprosium and terbium.

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Dysprosium is important and irreplaceable.

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However, far more dysprosium relative to neodymium is required than occurs naturally in the REE ores, meaning that another source of dysprosium must be found if hybrid cars are to be manufactured at a seriously advancing rate. 97% of REEs come from China, and it appears that China will run out of dysprosium within 15 years, or sooner if demand continues to soar.

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