Quick Search:    advanced search

GSW Home   GeoRef Home   My GSW Alerts   Contact GSW   About GSW   Journals List   Help

This Article Résumé Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Holtstam, D. Articles by Nysten, P. Search for Related Content GeoRef GeoRef Citation

HALENIUSITE-(La) FROM THE BASTNÄS DEPOSIT, VÄSTMANLAND, SWEDEN: A NEW REE OXYFLUORIDE MINERAL SPECIES

Dan Holtstam^1,, Jekabs Grins² and Per Nysten³

¹ Department of Mineralogy, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden
² Department of Inorganic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
³ Department of Earth Sciences, Uppsala University, Villavägen 16, SE-752 36 Uppsala, Sweden

E-mail address: dan.holtstam{at}nrm.se

Håleniusite-(La), a new mineral species whose ideal formula is (La,Ce)OF, is cubic and has a unit-cell parameter a equal to 5.6282(5) Å, V = 178.28(5) ų, for Z = 4. The strongest five lines in the X-ray powder-diffraction pattern obtained with a Guinier–Hägg camera [d in Å (I_obs)(hkl)] are: 3.25(100)(111), 2.815(31)(200), 1.991(61)(220), 1.697(46)(311) and 1.292(15)(331). The crystal structure was refined in space group Fm3m from powder data using the Rietveld method, to an R_F value of 5.1%. The mineral is shown to be isostructural with fluorite, and the average metal–anion distance is 2.437(1) Å for håleniusite-(La). D(calc.) 6.5 g/cm³. The atomic ratio La/(La + Ce) is 0.506 0.001 (range 0.485–0.528). Håleniusite-(La) is powdery, with a distinct yellow color. It is associated with bastnäsite-(La), brochantite, ferriallanite-(Ce) and quartz in the type specimen, and was found on the dumps of the Bastnäs Cu–REE mines in Västmanland, Sweden. Additional specimens from the same locality contain cerite-(Ce), molybdenite and amphibole. Håleniusite-(La) is a secondary mineral, formed by alteration of primary bastnäsite-(La), most likely via a decarbonation reaction, (La, Ce)CO₃F (La, Ce)OF + CO₂. The name of this new mineral honors Ulf Hålenius, Professor of Mineralogy at the Swedish Museum of Natural History.

Keywords: håleniusite-(La), new mineral species, REE oxyfluoride, lanthanides, Bastnäs, Sweden.

This article has been cited by other articles:

				K. Breiter, R. Copjakova, and R. Skoda THE INVOLVEMENT OF F, CO2, AND As IN THE ALTERATION OF Zr-Th-REE-BEARING ACCESSORY MINERALS IN THE HORA SVATE KATERINY A-TYPE GRANITE, CZECH REPUBLIC Can Mineral, December 1, 2009; 47(6): 1375 - 1398. [Abstract] [Full Text] [PDF]

				D. Holtstam and U. B. Andersson THE REE MINERALS OF THE BASTNAS-TYPE DEPOSITS, SOUTH-CENTRAL SWEDEN Can Mineral, October 1, 2007; 45(5): 1073 - 1114. [Abstract] [Full Text] [PDF]