J 2012

Allanite-(Nd), CaNdAl2Fe2+(SiO4)(Si2O7)O(OH), a new mineral from Askagen, Sweden

ŠKODA, Radek, Jan CEMPÍREK, Jan FILIP, Milan NOVÁK, Frantisek VESELOVSKY et. al.

Basic information

Original name

Allanite-(Nd), CaNdAl2Fe2+(SiO4)(Si2O7)O(OH), a new mineral from Askagen, Sweden

Authors

ŠKODA, Radek (203 Czech Republic, guarantor, belonging to the institution), Jan CEMPÍREK (203 Czech Republic), Jan FILIP (203 Czech Republic), Milan NOVÁK (203 Czech Republic, belonging to the institution), Frantisek VESELOVSKY (203 Czech Republic) and Radim CTVRTLIK (203 Czech Republic)

Edition

American Mineralogist, CHANTILLY, Mineralogical Society of America, 2012, 0003-004X

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

10500 1.5. Earth and related environmental sciences

Country of publisher

United States of America

Confidentiality degree

není předmětem státního či obchodního tajemství

Impact factor

Impact factor: 2.204

RIV identification code

RIV/00216224:14310/12:00057153

Organization unit

Faculty of Science

DOI

UT WoS

000304212900020

Keywords in English

Epidote supergroup; allanite; neodymium; pegmatite; Askagen

Tags

Tags

International impact, Reviewed
Změněno: 4/4/2013 07:39, prof. RNDr. Milan Novák, CSc.

Abstract

V originále

Allanite-(Nd), ideally CaNdAl2Fe2+(SiO4)(Si2O7)O(OH), the Nd-analog of allanite-(Ce), occurs in the Askagen pegmatite, central Sweden. It forms fine-grained aggregates within altered thalenite-(Y). The other associated minerals include: iimoriite-(Y), keiviite-(Y), allanite-(Y), and tengerite-(Y). Allanite-(Nd) is biaxial (-); with refractive indices alpha = 1.723(5), beta = 1.754(7), gamma = 1.772(5), and measured 2V = 82 degrees(+/- 3 degrees). Larger fragments of allanite-(Nd) are moderately pleochroic (alpha = pale grayish-brown, gamma = grayish-brown); small fragments are colorless. Allanite-(Nd) is monoclinic, space group P2(1)/m, with the following unit-cell parameters: a = 8.8897(5), b = 5.7308(2), c = 10.1010(6) angstrom, beta = 115.166(7)degrees, V = 465.75(4) angstrom(3), Z = 2. The strongest five peaks from the X-ray powder diffraction patterns [d (angstrom)(I)(hkl)] are: 3.51(46)((2) over bar 11), 2.89(100)((1) over bar 13), 2.87(45)(020), 2.70(60)(120), 2.61(60)((3) over bar 11). Allanite-(Nd) has a density of 3.98 g/cm(3), vitreous luster, grayish-brown streak, and the Mohs hardness is ca. 6. It is brittle, with imperfect cleavage, and conchoidal fracture. The Mossbauer spectroscopy revealed Fe3+/Fe-101 ratio of 0.27 in the type sample. The refined empirical formula of the crystal used for the structure determination is: Al(Ca0.957Mn0.043)Sigma(A2)(1.000)(Nd0.337Ca0.154Sm0.131Ce0.125Y0.112Gd0.062Pr0.051DY0.016La0.007Er0.005)(Sigma 1.000) M1(Al0.860Fe0.1403+)(Sigma 1.000)Al-M2(M3)(Fe(0.760)(2+)Al(0.112)Fer(0.070)(3+)Mg(0.058))(Sigma 1.000)(Si3O11.978)-Si-T1,2,3(OH)(1.032). The allanite-(Nd) was approved by CNMNC (IMA 2010-060).

Links

KJB301630801, research and development project
Name: Interakce metamiktních minerálů s hydrotermálnímy fluidy a její význam geologickém prostředí
Investor: Academy of Sciences of the Czech Republic, The interaction of metamict minerals and hydrothermal fluids and its significance in the geological environment
MUNI/A/1060/2009, interní kód MU
Name: Posílení a zkvalitnění tvůrčí činnosti studentů PřF v oborech matematika, fyzika a vědy o Zemi (Acronym: KVAS-MPG)
Investor: Masaryk University, Category A