sjældne jordarter

Ifølge US Geological Survey (USGS), er der 17 sjældne jordarters grundstoffer i det periodiske system.
De første 15 elementer begynder med atomnummer 57 (lanthanum) frem til elementet nummer 71 (lutetium), og dertil er der to yderligere elementer, yttrium og scandium, der har lignende egenskaber. Sjældne jordarter er ikke nødvendigvis særlig sjældne, men findes i lave eller små koncentrationer i jordskorpen. Sjældne jordarter er opdelt i to grupper: lette sjældne jordarter (lanthanum, cerium, praseodym, neodym, promethium, samarium) og tunge sjældne jordarter ( europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium og yttrium).
Nogle sjældne jordarter bruges i atomvåben og i militærforskning.
Nogle radioaktive sjældne jordarter er sporet i nedfald fra atomvåbenforsøg.
Se også: US Magnet Manufacturing Association ; konfliktmineraler ; Det militær-industrille kompleks ; mineraler ; Rare Earth Industry and Technology Association ; Råstofdirektoratet.


A historical geography of rare earth elements: From discovery to the atomic age.
/ : Julie Michelle Klinger. The Extractive Industries and Society 2 (2015) 572–580.
This article presents a historical geography of rare earth elements from their discovery to the atomic age with a focus on the period between 1880 and 1960 in order to lend greater depth to the growing body of scholarship on the relationship between rare earth elements and global political change. Drawing on archival and field research undertaken in the United States, China, Brazil, and Germany between 2011 and 2014, this article advances the following argument. Rare earth elements, and the production of geological knowledge about them, have entangled with contentious politics since their first industrial applications in the late 19th century. The historical geography of rare earth exploration and extraction is defined by a fundamental tension between the military-industrial necessity of these elements and the hazards associated with their production. This tension played a definitive role in international colonial, ColdWar, and atomic politics.
Bibliography of the Geology and Mineralogy of the Rare Earths and Scandium to 1971. / : John Wagstaff Adams, Eleanora R. Iberall, 1973.

CRS: Rare Earth Elements: The Global Supply Chain. / : Marc Humphries. 2013.
'There are 17 rare earth elements (REEs), 15 within the chemical group called lanthanides, plus yttrium and scandium. The lanthanides consist of the following: lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. Rare earths are moderately abundant in the earth’s crust, some even more abundant than copper, lead, gold, and platinum. While more abundant than many other minerals, REEs are not concentrated enough to make them easily exploitable economically. The United States was once self-reliant in domestically produced REEs, but over the past 15 years has become 100% reliant on imports, primarily from China, because of lower-cost operations.
U.S.-based Molycorp has begun production at its Mountain Pass mine and anticipates production at full capacity (19,050 metric tons) in 2014. Molycorp also operates a separation plant at Mountain Pass, CA, and sells rare earth concentrates and refined products from newly mined and previously mined above-ground stocks. Molycorp announced its purchase of Neo Materials Technology (renamed Moly Canada), a rare earth processor and producer of permanent magnet powders which has facilities in China.
Some of the major end uses for rare earth elements include use in automotive catalytic converters, fluid cracking catalysts in petroleum refining, phosphors in color television and flat panel displays (cell phones, portable DVDs, and laptops), permanent magnets and rechargeable batteries for hybrid and electric vehicles, generators for wind turbines, and numerous medical devices. There are important defense applications, such as jet fighter engines, missile guidance systems, antimissile defense, space-based satellites and communication systems. World demand for rare earth elements was estimated at 136,000 tons per year, with global production around 133,600 tons in 2010. The difference was covered by previously mined aboveground stocks. World demand is projected to rise to at least 160,000 tons annually by 2016 according to the Industrial Minerals Company of Australia.'

Grasso, Valerie Bailey : Rare Earth Elements in National Defense: Background, Oversight Issues, and Options for Congress. CRS, March 31, 2011.
Marfelt, Birgitte: Sjældne jordmetaller sætter Grønland på verdens energikort : Grønland rummer sandsynligvis verdens største depot af sjældne jordmetaller, der i så fald kan dække en fjerdedel af det globale behov. I: Ingeniøren, 05/20/2011.
The Principal Rare Earth Elements Deposits of the United States — A Summary of Domestic Deposits and a Global Perspective. / : Keith R. Long et al. U.S. Department of the Interior U.S. Geological Survey, 2010.
Section 843 of the National Defense Authorization Act for Fiscal Year 2010, Public Law 111-84, directs the Comptroller General to complete a report on REE materials in the defense supply chain. The Office of Industrial Policy, in collaboration with other U.S. Government agencies, has initiated (in addition to this report) a detailed study of REE. This latter study will assess the Department of Defense’s use of REE, as well as the status and security of domestic and global supply chains. That study will also address vulnerabilities in the supply chain and recommend ways to mitigate any potential risks of supply disruption. To help conduct this study, the Office of Industrial Policy asked the U.S. Geological Survey (USGS) to report on domestic REE reserves and resources in a global context. To this end, the enclosed report is the initial USGS contribution to assessing and summarizing the domestic REE resources in a global perspective.
Venbjerg Hansen, Casper: Den globale kamp om sjældne jordarter er begyndt : Over de seneste par år er det blevet mere og mere klart, at adgangen til de sjældne jordarter er blevet et af de mest kritiske omdrejningspunkter for den grønne industri både i dag og i fremtiden. I Arbejderen, 08/03/2011

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