Norra Kärr

Norra Kärr or Norra Kärr Alkaline Complex is an intrusive complex cropping out at the boundary between Östergötland and Småland, Sweden.[1][2] The complex is chiefly made up of peralkaline nepheline syenite and is rich in exotic minerals.[1] Rocks of the complex intruded into the Paleoproterozoic-aged Växjo granites of the Transscandinavian Igneous Belt.[1][2] Alfred Elis Törnebohm was the first to describe the rocks of Norra Kärr in 1906. Norra Kärr was discovered a few years earlier during regional geological maping by the Swedish Geological Survey. The complex derives its name from a local farm, which translates into English as "Northern Fen".[2] In 1968 Harry von Eckermann published his investigations on the complex defining its boundaries and confirming the view of it as an intrusion.[3]

A study has shown that the elevated rare-earth element concentrations in the bedrock in the Norra Kärr area are particularly well reflected in high contents of these elements in the fern Dryopteris filix-mas. This raises the possibility for the fern species to be used in biogeochemical prospecting.[4]

Norra Kärr is one of the two known sites where the mineral jinshajiangite can be found naturally, the other being in China.[5][6]

Mine project
Norra Kärr mine
Location
Jönköping County
CountrySweden
Production
ProductsRare earth elements, for example Zirconium

The Norra Kärr mine project represents one of the largest zirconium reserves in Sweden having estimated reserves of 58 million tonnes of ore grading 1.7% zirconium metal.[7]

Since 2009, the Canadian company Tasman Metals has owned the mining rights and explored for rare earth elements in the Norra Kärr area.[8][1]

In February 2016 the supreme administrative court of Sweden withdrew Tasman's exploitation concession for Norra Kärr.

References
  1. "Report on the Geology, Mineralization and Exploration Potential of the Norra Kärr Zirconium-REE Deposit, Gränna, Sweden" (PDF). Tasman Metals Ldt. Archived from the original (PDF) on 2014-02-07. Retrieved 2013-01-04.
  2. Sjöqvist, Axel S.L.; Cornell, David H.; Andersen, Tom; Erambert, Muriel; Ek, Mattias; Magnus, Leijd (2013). "Three Compositional Varieties of Rare-Earth Element Ore: Eudialyte-Group Minerals from the Norra Kärr Alkaline Complex, Southern Sweden". Minerals. 3 (1): 94–120. doi:10.3390/min3010094.
  3. von Eckermann, Harry (1968). "New contributions to the interpretation of the genesis of the Norra Kärr alkaline body in Southern Sweden". Lithos. 1 (1): 76–88. doi:10.1016/S0024-4937(68)80037-4.
  4. Bluemel, Britt; Leijd, Magnus; Dunn, Colin; Hart, Craig J.R.; Saxon, Mark; Sadeghi, Martiya (2013). "Biogeochemical expression of rare earth element and zirconium mineralization at Norra Kärr, Southern Sweden" (PDF). Journal of Geochemical Exploration. 133 (15–24).
  5. Holtstam, Dan (1998). "Jinshajiangite from the Norra Kärr alkaline intrusion, Jönköping, Sweden". GFF. 120 (4): 373–374. doi:10.1080/11035899801204373.
  6. Rastsvetaeva, R.K.; Chukanov, N.V.; Rozenberg, K.A. (2008). "Crystal Structure of Jinshajiangite from the Norra Kärr Complex (Sweden)". Crystallography Reports. 53 (4): 553–556. doi:10.1134/S1063774508040044.
  7. "Norra Kärr mine" (PDF). tasmanmetals.com. 2012. Retrieved 2013-07-05.
  8. "Gränna kan bli nästa gruvort". Archived from the original on 2012-10-18. Retrieved 2017-07-26.


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