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Hundholmenite-(Y) from Norway – a new mineral species in the vicanite group: descriptive data and crystal structure

Published online by Cambridge University Press:  05 July 2018

G. Raade*
Affiliation:
Department of Geology, Natural History Museum, University of Oslo, P.O. Box 1172 Blindern, NO-0318 Oslo, Norway
O. Johnsen
Affiliation:
Geological Museum, University of Copenhagen, Øster Voldgade 5-7, DK-1350 København K, Denmark
M. Erambert
Affiliation:
Department of Geosciences, University of Oslo, P.O. Box 1047 Blindern, NO-0316 Oslo, Norway
O. V. Petersen
Affiliation:
Geological Museum, University of Copenhagen, Øster Voldgade 5-7, DK-1350 København K, Denmark
*

Abstract

Hundholmenite-(Y) occurs as pale brown, subhedral crystals up to 1 mm across, embedded in REE–bearing fluorite, in a granitic pegmatite at Hundholmen, Tysfjord, Nordland County, north Norway. Two other occurrences in the same area are the granitic pegmatites at Stetind and Lagmannsvik. The simplified formula, obtained from wavelength-dispersive EMP analyses and boron determination by ICP-AES, is (Y,REE,Ca,Na)15(Al,Fe3+)CaxAs1–x3+ (Si,As5+)Si6B3(O,F)48 (x = 0.78). The mineral is trigonal, R3m, with a = 10.675(6), c = 27.02(2) Å , V = 2667(5) Å 3, Z = 3. The crystal structure was refined to R1 = 0.037 for 1720 observed reflections. Hundholmenite-(Y) is isostructural with okanoganite-(Y) and vicanite-(Ce), and the differences in site populations are discussed. The strongest seven reflections of the X-ray powder-diffraction pattern [dobs in Å , (I) (hkl)] are: 4.38 (33) (202), 3.114 (43) (214), 2.972 (100) (027), 2.947 (76) (125), 2.924 (66) (303, 033), 2.681 (36) (220) and 1.978 (37) (235). The mineral is optically uniaxial (–) with o 1.7578(5) and e 1.7487(5). The Mohs hardness is ~5–6; Dcalc = 5.206(9) g/cm3.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2007

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References

Andresen, A. and Tull, J.F. (1986) Age and tectonic setting of the Tysfjord gneiss granite, Efjord, North Norway. Norsk Geologisk Tidsskrift, 66, 69–80.Google Scholar
Ballirano, P., Callegari, A., Caucia, F., Maras, A., Mazzi, F. and Ungaretti, L. (2002) The crystal structure of vicanite-(Ce), a borosilicate showingan unusual (Si3B3O18)15- polyanion. American Mineralogist, 87, 1139–1143.CrossRefGoogle Scholar
Boggs, R.C. (1980) Okanoganite, a new rare-earth borofluorosilicate from the Golden Horn batholith, Okanogan County, Washington. American Mineralogist, 65, 1138–1142.Google Scholar
Boiocchi, M., Callegari, A., Ottolini, L. and Maras, A. (2004) The chemistry and crystal structure of okanoganite-(Y) and comparison with vicanite- (Ce). American Mineralogist, 89, 1540–1545.CrossRefGoogle Scholar
Brese, N.E. and O'Keeffe, M. (1991) Bond-valence parameters for solids. Acta Crystallographica, B47, 192–197.Google Scholar
Bruker AXS (1998) SMART. Bruker Analytical X-ray Systems. Madison, Wisconsin, USA.Google Scholar
Fischer, R.X. and Tillmanns, E. (1988) The equivalent isotropicdis placement factor. Act a Crystallographica, C44, 775–776.Google Scholar
Foslie, S. (1941) Tysfjords geologi. Beskrivelse til det geologiske gradteigskart Tysfjord. Norges Geologiske Undersøkelse, 149, 298 pp, Plates I–XVI.Google Scholar
Graeser, S., Schwander, H., Demartin, F., Gramaccioli, C.M., Pilati, T. and Reusser, E. (1994) Fetiasite (Fe2+,Fe3+,Ti)3O2[As2O5], a new arsenite mineral: Its description and structure determination. American Mineralogist, 79, 996–1002.Google Scholar
Jarosewich, E. and Boatner, L.A. (1991) Rare-earth element reference samples for electron microprobe analysis. Geostandards Newsletter, 15, 397–399.CrossRefGoogle Scholar
Laugier, J. and Bochu, B. (2002) CELREF V3: Cell parameters refinement program from powder diffraction diagram. Laboratoire des Matériaux et du Génie Physique, Institut National Polytechnique de Grenoble, France. http://www.ccp14.ac.uk/tutorial/lmgp/celref–sgdetermine.htm Google Scholar
Mandarino, J.A. (1981) The Gladstone–Dale relationship: Part IV. The compatibility concept and its application. The Canadian Mineralogist, 19, 441–450.Google Scholar
Maras, A., Parodi, G.C., Della Ventura, G. and Ohnenstetter, D. (1995) Vicanite-(Ce): A new Ca- Th-REE borosilicate from the Vico volcanic district (Latium, Italy). European Journal of Mineralogy, 7, 439–446.CrossRefGoogle Scholar
McDonough, W.F. and Sun, S.-S. (1995) The composition of the Earth. Chemical Geology, 120, 223–253.CrossRefGoogle Scholar
Medenbach, O. (1985) A new microrefractometer spindle stage and its application. Fortschritte der Mineralogie, 63, 111–133.Google Scholar
Nilssen, B. (1973) Contribution to the mineralogy of Norway, No. 55. Gadolinite from Hundholmen, Tysfjord, north Norway. Norsk Geologisk Tidsskrift, 53, 343–348.Google Scholar
Raade, G., Kolitsch, U. and Husdal, T.A. (2006) Si-rich bergslagite from a granitic pegmatite at Tennvatn, north Norway. GFF, 128, 65–68.CrossRefGoogle Scholar
Sheldrick, G.M. (1993) SHELXL-93. Program for the Refinement of Crystal Structures. University of Göttingen, Germany.Google Scholar
Sheldrick, G.M. (1997) SHELXS-97. Program for the Solution of Crystal Structures. University of Göttingen, Germany.Google Scholar
Strunz, H. and Nickel, E.H. (2001) Strunz Mineralogical Tables, Ninth Edition. E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany, 870 pp.Google Scholar
Sverdrup, T.L. (1968) Contributions to the mineralogy of Norway, No. 37. Yttrofluorite–yttrocerite–cerfluorite in Norwegian pegmatites. Norsk Geologisk Tidsskrift, 48, 245–252.Google Scholar
Vogt, T. (1911) Vorläufige Mitteilung über Yttrofluorit, eine neue Mineralspezies aus dem nördlichen Norwegen. Centralblatt fürMiner alogie, Geologie und Paläontologie, 373–377.Google Scholar
Vogt, T. (1922) Über Thalenit von Hundholmen im nördlichen Norwegen. Videnskapsselskapets Skrifter. I. Matematisk-naturvidenskapelig Klasse. 1922. No. 1, 19–47, Plates VII–IX.Google Scholar