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Grice J.D.,Canadian Museum of Nature | Friis H.,University of Oslo | Kristiansen R.,PO Box 32
Canadian Mineralogist | Year: 2016

Chiavennite (Mn endmember) and ferrochiavennite (Fe endmember) are beryllium silicate zeolites with chemical compositions close to Ca1-2(Mn,Fe)Si5Be2O13(OH)2•2H2O. Five chiavennite crystals from four different localities, Chiavenna, Italy; Telemark, Norway; Uto, Sweden; and Ambatovita, Madagascar, were chosen for crystal-structure analysis. Initially all had been reported to be orthorhombic, but all are monoclinic, with a β angle near 90°, as is ferrochiavennite from Blafjell, Norway. Twinning on {100} is common. Chiavennite and ferrochiavennite are isostructural. The zeolite structure consists of intersecting channels of nine-, six-, five-, and four-fold rings. All five structures have one Ca site in common while chiavennite from Uto and ferrochiavennite from Bl afjell have a second, partially filled, Ca site. Hydrogen atoms were located in all five structures. Hydrogen bonding is similar but not identical in all five structures. The H atoms associated with BeO4 tetrahedra act as terminations to a polymerization sequence causing chiavennite and ferrochiavennite to be interrupted zeolite structures.

Grice J.D.,Canadian Museum of Nature | Kristiansen R.,PO Box 32 | Friis H.,University of Oslo | Rowe R.,Canadian Museum of Nature | And 4 more authors.
Canadian Mineralogist | Year: 2017

Hydroxylgugiaite, ideally (Ca3A1)R4(Si3.5Be2.5)R6O11(OH)3, is a new mineral species from two localities in the Larvik plutonic complex in Porsgrunn, Telemark, Norway, and one locality in Iĺimaussaq, Greenland. Hydroxylgugiaite crystals occur as squat dipyramids {111} (30 × 50 μm) or as elongate tetragonal prisms. The crystals are translucent, white to pale grey in color, with a white streak and vitreous luster. It is brittle, with no apparent cleavage. Hydroxylgugiaite is uniaxial positive with ω = 1.622 ± 0.002 and ϵ = 1.632 ± 0.002. There is no pleochroism and birefringence is low. The average of eight analyses of a single grain of type material (oxide wt.%) gave Na2O 2.04, CaO 32.90, FeO 0.22, MnO 0.74, BeO 13.47 (LA-ICP-MS), Al2O3 0.74, SiO2 44.06, F 1.74, H2O (assuming 3 OH + F) 4.93, Total (-0.73 O = F) 100.10. Potassium, strontium, and magnesium were measured but not detected. The calculated density is 2.79 g cm-3. The empirical formula on the basis of 14 anions including 3 OH- + F- is: (Ca2.76Na0.31Mn0.05Fe0.01)R3.13(Si3.45Be2.53Al0.07)R6.05O11[(OH)2.57F0.43]R3. The formula from crystal-structure analysis of the Saga specimen is: (Ca3.02A0.98)R4(Si1.79Be0.21)R2(Be2.29Si1.71)R4O11(OH)3. Combined structural and chemical data gives the fol lowing formula for the Nakkaalaaq specimen: (Ca2.88A0.98Na0.12Mn0.02)R4(Si1.80Be0.17Al0.03)R2 (Be2.32Si1.68)R4O11[(OH)2.70F0.30]R3; with simplified formula (Ca,A)4(Si,Be)2(Be,Si)4O11(OH)3. The crystal structure of hydroxylgugiaite is tetragonal in acentric space group P421/m, with a 7.4151(2), b 7.4151, c 4.9652(1) Å, V 272.9(1) Å3, and Z=1. It has been refined to an R index of 0.028 on the basis of 342 observed reflections and a correction for the {110} twin law. It is an H-bearing member of the melilite group. The structure has two distinct layers. The one crystallographically distinct Ca site with eight-fold coordination is a square antiprism polyhedron. The Ca polyhedra are in a layer with the H atoms. A second layer consists of corner-sharing Si/Be atoms in tetrahedral coordination with O. One H atom is bonded to an apical O atom that is not shared by two tetrahedra. This H atom is present only when there is a Ca-site vacancy. The other H atom is loosely bonded to the same O atom but at a different site. The IR spectrum supports this H-bonding scheme. Additional hydroxylgugiaite data is given for the other localities.

Bos D.,P.O. Box 32 | Bos D.,University of Groningen | Ydenberg R.,Wageningen University | Ydenberg R.,Simon Fraser University
Wildlife Biology | Year: 2011

Muskrats Ondatra zibethicus are considered a pest species in the Netherlands, and a year-round control programme is in effect. Currently, the agency responsible for the management of muskrat populations in the Netherlands (the LCCM) is preparing for field studies to compare alternative strategies of control. In order to decide on the specific design of such field studies, a population dynamic model was built. The model compares the current management strategy with alternatives in which the effort is focused in space or in time. The model allows us to prioritise future research questions. The major gaps in knowledge at this moment are: 1) insight into the costs of harvesting at different harvest rates, and 2) the relationship between population density on the one hand and (financial damage or) safety risk on the other hand. We suggest continuing the current management, and to test our hypothesis that intensifying harvest will lead to lower numbers of animals killed in the medium term than more extensive harvest rates. The muskrat control programme offers excellent opportunities for applied biological studies of which the benefits are likely to outweigh the costs. © Wildlife Biology, NKV.

Kolitsch U.,Mineralogisch Petrographische Abt. | Kristiansen R.,PO Box 32 | Raade G.,University of Oslo | Tillmanns E.,University of Vienna
European Journal of Mineralogy | Year: 2010

Heftetjernite,ideally ScTaO4, is a new scandium mineral from the Heftetjern pegmatite, T0ℝ, Telemark, Norway. In the type specimen, it occurs as minute, elongate tabular, very dark brown crystals in a single small void in albite. Other associated minerals are fluorite, muscovite, altered milarite, a metamict, dark greyish brown mineral of the pyrochlore-microlite group, and an unidentified, orange-brown, tabular, nearly X-ray amorphous Ti-Y-Ta-Nb-mineral. Electron-microprobe analysis yielded the empirical formula (Sc0.64Sn0.13Mn0.12Fe0.08Ti 0.06)σ1.03(Ta0.69Nb0.30) σ0.99O4 which clearly demonstrates the charge-balanced substitution scheme 2Sc3+ = (Sn,Ti)4+ + (Mn,Fe)2+. Themineral crystallises in the wolframite structure type, with space group P2/c and a= 4.784(1), b= 5.693(1), c = 5.120(1) Å , β = 91.15(3)-B, V = 139.42(5) Å 3 (Z = 2). A synthetic equivalent is known. Strongest lines in the calculated X-ray powder diffraction pattern of heftetjernite are [d in Å (I) (hkl)]: 3.000 (100) (11-1), 2.9570 (97) (111), 3.662 (53) (110), 2.4877 (34) (02-1), 4.783 (33) (100), 3.807 (32) (01-1). The crystal structure was refined to R(F)= 1.39%from single-crystal X-ray diffraction data (293 K). It is based on two types of edge-sharing, distorted octahedra occupied predominantly by Sc and Ta, respectively. Heftetjernite is translucent to transparent, with a dark brownish (with a reddish hue) streak and adamantine lustre. It is brittle, has a perfect {010} cleavage, irregular fracture and a Mohs hardness estimated to be around 4.5 by comparison to ferberite; Dx = 6.44 g/ cm3 (from crystal-structure analysis). Optically, the mineral is biaxial with an unknown optical sign, weakly pleochroic (yellowish brown with a reddish tint to reddish brown), with no observable dispersion. A mean refractive index of 2.23 was calculated from the Gladstone-Dale relationship using the X-ray density. Heftetjernite is named after its type locality. The mineral is compared with synthetic ScTaO 4, ScNbO4, iwashiroite-(Y) and formanite-(Y) (both nominally YTaO4), and some comments are made on the relation to Sc-bearing ixiolite. © 2010 E. Schweizerbart'sche Verlagsbuchhandlung.

Grice J.D.,Canadian Museum of Nature | Kristiansen R.,PO Box 32 | Friis H.,University of Oslo | Rqwe R.,Canadian Museum of Nature | And 4 more authors.
Canadian Mineralogist | Year: 2013

Ferrochiavennite is a new beryllium silicate zeolite with chemical composition close to CaM1-2FeSi5Be2O 13(OH)2,2H2O. It is described from two syenite pegmatite localities in Norway: Blafjell, Langangen, Telemark, and the AS Granit larvikite quarry, Tvedalen, Vestfold. The mineral is monoclinic, P2 /c, with a 8.759(5), b 4.864(2), c 31.258(6) Å, p 90.31(6)°, V 1331.7(6) Å3, and Z = 4. The crystal structure was refined to R1 = 0.048 for 3651 observed reflections. The zeolite structure is isostructural with chiavennite, consisting of intersecting channels of nine-, six-, five-, and four-fold rings. The strongest eight reflections of the X-ray powder-diffraction pattern [d(obs.) in Å (I) (hkl)] are: 15.555 (100) (002), 4.104 (29) (11̄2, 112), 3.938 (36) (11̄3, 113), 3.909 (60) (008), 3.820 (30) (2̄04, 204), 3.251 (66) (017, 210, 2̄11), 3.186 (27) (2̄12, 212), 2.884 (64) (2̄15, 215). The mineral is biaxial (+) with refractive indices a 1.583(1), β 1.589(1), γ 1.602(1), measured at 590 nm. 2V (meas.) = 62(4)° from extinction curves 2V = 76(5)°; 2V (calc.) = 69°. The optical orientation is X ∼ a, Y ∼ c, and Z ∼ b. The Mohs hardness is ∼ 3; D(meas.) = 2.67(2) and D(calc.) = 2.709 g/cm3..

Oberti R.,CNR Institute of Geosciences and Earth Resources | Boiocchi M.,University of Pavia | Hawthorne F.C.,University of Manitoba | Kristiansen R.,PO Box 32
Mineralogical Magazine | Year: 2014

A second occurrence of ferri-fluoro-leakeite has been identified in the Bratthagen nepheline syenite pegmatite (Vestfold County, Norway). With respect to the holotype found at the Verkhnee Espe deposit (Akjailyautas Mountains, Kazakhstan; Cámara et al., 2010), it is closer to the ideal composition because of its larger Li and Mg contents and the absence of an oxo-component; however, it has a significant Zn content (0.29 a.p.f.u.). The ideal formula of ferri-fluoro-leakeite is ANaBNa2 C(Mg2Fe3+ 2Li)TSi8O22 WF2 and the empirical formula derived from electron-microprobe analysis and single-crystal structure refinement for the sample used here is A(Na0.68K0.32)=1.00 BNa2.00 C(Mg1.69Mn2+ 0.25Fe2+ 0.24Zn 0.29Al0.23Fe3+ 1.50Ti0.02Li0.78)=5.00 TSi8O22 W(F1.59(OH)0.41)=2.00. Unitcell data are a = 9.788(2), b = 17.826(3), c = 5.282(1) Å, β = 104.195(5)°, V = 893.5 (3) Å3, Z = 2. Crystal-chemical analysis shows that Li is ordered at the M(3) site and Zn is ordered mainly at the M(2) site, confirming previous findings for Li-bearing amphiboles. The new data also make quantification of the oxo component in Na amphiboles possible. © 2014 Mineralogical Society.

Hawthorne F.C.,University of Manitoba | Abdu Y.A.,University of Manitoba | Ball N.A.,University of Manitoba | Cerny P.,University of Manitoba | Kristiansen R.,PO Box 32
American Mineralogist | Year: 2014

Agakhanovite-(Y), ideally (YCa)KBe3Si12O30, is a new milarite-group mineral from the Heftetjern pegmatite, Tørdal, southern Norway. Crystals are prismatic along [001], and show the forms {100} and {100}. Agakhanovite-(Y) is colorless with a white streak and a vitreous luster, and does not fluoresce under ultraviolet light. There is no cleavage or parting, and no twinning was observed. Mohs hardness is 6, and agakhanovite-(Y) is brittle with a conchoidal fracture. The calculated density is 2.672 g/cm3. Optical properties were measured with the Bloss spindle stage for the wavelength 590 nm using a gel filter. Agakhanovite-(Y) is uniaxial (-) with indices of refraction w = 1.567, e = 1.564, both ±0.002; the calculated birefringence is 0.003 and it is non-pleochroic. Agakhanovite-(Y) is hexagonal, space group P6/mcc, a = 10.3476(2), c = 13.7610(3) Å, V = 1276.02(9) Å3, Z = 2, c:a = 1.330. The seven strongest lines in the X-ray powder-diffraction pattern are as follows: d (Å), I, (hkl): 2.865, 100, (124); 3.287, 96, (131); 4.134, 84, (122); 6.877, 56, (002); 2.986, 43, (030); 4.479, 38, (020); 2.728, 36, (024). Chemical analysis by electron microprobe gave SiO2 69.56, Al2O3 0.35, Y2O3 9.69, Yb2O3 0.15, FeO 0.02 CaO 5.75, Na2O 0.07, K2O 4.52, BeO(calc) 7.06, H2O(calc) 1.74, sum 98.91 wt%. The H2O content was determined by crystal-structure analysis. On the basis of 30 anions, the empirical formula is (Y0.89Yb0.01Ca1.06)S1.96(H2O)0.92Na0.02K1.00(Be2.93Al0.07)S3.00Si12.02O30. The crystal structure of agakhanovite-(Y) was refined to an R1 index of 1.9% based on 660 unique observed reflections collected on a three-circle rotating-anode (MoKa X-radiation) diffractometer equipped with multilayer optics and an APEX-II detector. In the end-member structure of agakhanovite-(Y), the A site is occupied equally by Y and Ca, and the B site is vacant; agakhanovite-(Y) is the Y-analog of oftedalite: ScCaKBe3Si12O30, and the Y-Ca-Be analog of klöchite, (Fe2+Fe3+)KZn3Si12O30. © 2014 by Walter de Gruyter Berlin/Boston.

Miyawaki R.,National Museum of Nature and Science | Momma K.,National Museum of Nature and Science | Yokoyama K.,National Museum of Nature and Science | Shigeoka M.,National Museum of Nature and Science | And 4 more authors.
Canadian Mineralogist | Year: 2015

Mn-bearing hellandite-(Y) occurs as pinkish yellow granular crystals (up to sub mm) in the Sc-rich granite pegmatite at Heftetjern, Tørdal, Telemark, Norway. Associated minerals are quartz, albite, Sc- and Ce-bearing epidote, hingganite-(Y), and an undetermined Ca-bearing hingganite-related mineral. Electron microprobe analyses give an empirical formula as Ca1.34Mn1.07Y2.75Ce0.02Nd0.02Sm0.01Gd0.01Dy0.05Er0.05Yb0.15Al0.94Fe0.08Si3.99B4.33O22.00 (OH)2.00 on the basis of Al+Fe+Si = 5 and 24 anions per formula unit. The lattice parameters were refined from diffraction data obtained using a Gandolfi camera with an imaging plate and Ni filtered CuKα; a 18.693(17), b 4.651(3), c 10.178(7) A, β = 111.37(6)°, V 824.1(10) A3. The crystal structure was refined from single-crystal XRD data obtained with a CCD-diffractometer and graphite-monochromated MoKα. The refinement with anisotropic atomic displacement parameters converged to R1 = 0.0269 for 1567 reflections [I > 2σ(I)] and 0.0318 for all 1768 reflections, resulting in the structural formula M3(Ca0.56Mn0.44)2 M4(Y0.43 Ca0.23Ln0.14 0.20)2 M2(Y0.94Ln0.06)2 M1(Al0.92Fe0.08)Si4B4O21.21 (OH)2.79. In this hellandite-(Y), Mn2+ replaces Ca2+ at the M3 site and there is a significant vacancy at the M4 site. The T site is vacant, and, instead, the O5 position is occupied by (OH)-.

Cooper M.A.,University of Manitoba | Abdu Y.A.,University of Manitoba | Ball N.A.,University of Manitoba | Cerny P.,University of Manitoba | And 2 more authors.
Canadian Mineralogist | Year: 2012

Aspedamite, ideally □ 12(Fe 3+,Fe 2+) 3Nb 4[Th(Nb,Fe 3+) 12O 42]{(H 2O), (OH)} 12, is a new heteropolyniobate mineral species from the Herrebøkasa quarry, Aspedammen, østfold, southern Norway. It occurs as small euhedral crystals of dodecahedra and cubes to a maximum of 50 μm across, perched on a white mat of an Al-Nb-Fe-Ti-Ca-K-bearing silicate on a partly altered 12 × 12 × 6 mm crystal of monazite penetrated by plates of columbite-(Fe) and muscovite. Aspedamite is brownish orange with a very pale orange streak and an adamantine luster; it does not fluoresce under ultraviolet light. The Mohs hardness is 3-4, and it is brittle with a hackly fracture. The calculated density is 4.070 g/cm 3, and the calculated index of refraction is 2.084. Aspedamite is cubic, space group Im3̄, a 12.9078(6) Å, V 2150.6(3) Å 3, Z = 2. The strongest seven lines in the X-ray powder-diffraction pattern [d in Å(I)hkl] are: 9.107(100)011, 2.635(36)224, 2.889(33)024, 1.726(29)246, 3.233(28)004, 3.454(18)123, 4.567(15)022. A chemical analysis with an electron microprobe gave Nb 2O 5 65.64, Ta 2O 5 1.78, SiO 2 0.78, ThO 2 5.64, TiO 2 2.15, Fe 2O 3 10.56, FeO 2.73, MnO 0.82, CaO 0.28, K 2O 0.16, La 2O 3 0.52, Ce 2O 3 1.62, Nd 2O 3 0.44, H 2O (calc) 7.20, sum 100.32 wt.%; the H 2O content was determined by crystal-structure analysis. The empirical formula of aspedamite on the basis of 54 anions with Fe 3+/(Fe 3+ + Fe 2+) = 0.67 (estimated from crystal-chemical arguments) and O(4) = (H 2O)9 + (OH) 3 is K0.09 Ca 0.13Ce 0.26La 0.08Nd 0.07Fe 2+ 1.00Mn 0.30Fe 3+ 3. 48Th 0.56Ti 4+ 0.71Si 0.34Nb 12.98Ta 0.21O 42(H 2O)9(OH) 3. The crystal structure of aspedamite was solved by direct methods and refined to an R 1 index of 1.6% based on 596 observed reflections collected on a three-circle rotating-anode (MoKα X-radiation) diffractometer equipped with multilayer optics and an APEX-II detector. The structure is based on the heteropolyanion [DA 12O 42] (D = Th, sum A = Nb 9Fe 3+ 2Ti), which consists of twelve face - and corner-sharing AO 6 octahedra that surround the [12]-coordinated D cation. There are eight heteropolyanions at the corners of the unit cell, with an additional heteropolyanion at the center, forming an I-centered arrangement. Each heteropolyhedral cluster is decorated by eight B octahedra, each of which bridges two adjacent clusters along the body diagonals of the cell. Further intercluster linkage is provided by the C octahedra, which link pairs of adjacent clusters in the a direction. Aspedamite is isostructural with menezesite.

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