Zirconolite from Larvik Plutonic Complex, Norway, its
relationship to stefanweissite and nöggerathite, and
contribution to the improvement of zirconolite endmember
systematics

J 2021

Zirconolite from Larvik Plutonic Complex, Norway, its relationship to stefanweissite and nöggerathite, and contribution to the improvement of zirconolite endmember systematics

HAIFLER, Jakub, Radek ŠKODA, Jan FILIP, Alf Olav LARSEN, Jan ROHLÍČEK et. al.

Základní údaje

Originální název

Zirconolite from Larvik Plutonic Complex, Norway, its relationship to stefanweissite and nöggerathite, and contribution to the improvement of zirconolite endmember systematics

Autoři

HAIFLER, Jakub (203 Česká republika, garant, domácí), Radek ŠKODA (203 Česká republika, domácí), Jan FILIP, Alf Olav LARSEN a Jan ROHLÍČEK

Vydání

American Mineralogist, Mineralogical Society of America, 2021, 0003-004X

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

10504 Mineralogy

Stát vydavatele

Spojené státy

Utajení

není předmětem státního či obchodního tajemství

Odkazy

URL

Impakt faktor

Impact factor: 3.066

Kód RIV

RIV/00216224:14310/21:00121289

Organizační jednotka

Přírodovědecká fakulta

DOI

http://dx.doi.org/10.2138/am-2021-7510

UT WoS

000679806000006

Klíčová slova anglicky

zirconolite; stefanweissite; nöggerathite; polymignyte; Larvik Plutonic Complex; metamict; endmember; composition space; substitution; Rietveld refinement

Štítky

rivok

Příznaky

Mezinárodní význam, Recenzováno

Změněno: 6. 9. 2021 09:33, Mgr. Marie Šípková, DiS.

Anotace

V originále

The very first description of zirconolite, originally called polymignyte, discovered in alkaline pegmatites within the Larvik Plutonic Complex (LPC), Norway, was published almost 200 yr ago. We studied zirconolite from three occurrences located in this region using modern techniques-X-ray powder diffraction (XRPD) upon thermal annealing of initially radiation-damaged mineral, electron probe microanalysis, and Mossbauer spectroscopy. The initial XRPD pattern lacked any sharp diffraction maxima, as the accumulated radiation dose exceeded a critical value of ca. 10(16) alpha-decays/mg. Annealing at 400-800 degrees C induced recrystallization to a transitional, cubic phase interpreted to have a disordered, defect fluorite structure [space group Fm (3) over barm; unit-cell parameters: a = 5.1047(4) angstrom, V = 133.02(2) angstrom(3)], with its XRPD pattern being very similar to that of cubic ZrO2. Rietveld analysis of the XRPD pattern obtained after a phase transition at 900 degrees C shows a mixture of -30 [wt. fraction of ca. 60%, space group Cmca, unit-cell parameters: a = 7.2664(8) angstrom, b = 14.1877(15) angstrom, c = 10.1472(12) angstrom, V = 1046.1(2) angstrom(3)], and -3T [wt. fraction of ca. 40%, space group P3(1)21, unit-cell parameters: a = 7.2766(6) angstrom, c = 17.0627(15) angstrom, V = 752.42(11) angstrom(3)] zirconolite polytypes. However, the crystal habits of zirconolite from the LPC show a distinct orthorhombic symmetry. Although their chemical compositions are far from the ideal zirconolite composition and a large number of elements are involved in high concentrations [up to ca. 17 wt% REE2O3, <= 7 wt% ACTO(2), <= 18 wt% Me25+O5, <= 9 wt% Me2-O + Me23+O3, Fe3+/(Fe3++Fe2+) approximate to 0.2, where ACT = Th + U, Me5+ = Nb +/- Ta, Me2+ = Fe2+ +/- Mg, Me3+ approximate to Fe3+], the compositional variability is relatively limited. To quantitatively describe the two distinct compositional trends observed, we introduced a concept called "edgemembers," so that mixing is approximated to occur between two terminal compositions situated at two edges of the zirconolite composition space. These marginal compositions were determined from observed compositional trends, i.e., heterovalent substitution of Me5+ for Ti in octahedral sites and ACT enrichment associated with increasing Ti/Me5+ ratio. This approach provides general substitution vectors for both, Hakestad-type mode (ACT + 3 Ti + Me3+ = Ca + 3 Me5+ + Me2+), and Stalaker-type mode (0.7 ACT + 0.5 REE + 0.9 Ti + 0.7 Me3+ + 0.05 Zr = 1.2 Ca + 1.3 Me5+ + 0.3 Me2(+) + 0.05 Mn). In terms of chemical composition, the studied zirconolite corresponds to recently approved zirconolite-related minerals stefanweissite (for Ca > REE) and noggerathite (for REE > Ca). Based on a careful analysis of zirconolite composition space, we show that our observed HAkestad-type compositional trend, as well as a high number of published zirconolite compositions worldwide (with Me2+ + Me3+ sum of ca. 1 atom per 14 O), can be well approximated by a modified end-member set comprising Ca2Zr2Me25+TiMe2+O14, REE2Zr2Ti3Me2+O14, CaACTZr(2)Ti(3)Me(2+)O(14), CaREEZr2Ti3Me3+O14, Ca2Zr2Ti2Me5+Me5+O14 without a need to involve the ideal zirconolite formula Ca2Zr2Ti4O14. The redefined composition space constrained by end-members from this set, together with ideal zirconolite, may be representative of the vast majority of more than 450 published zirconolite compositions worldwide with Me2++Me3+ totaling <= 1 atom per 14 O. The equation XMe3+ = 2 - 2X(REE*) - 3(XMe)(5)(+*) provides an independent calculation of iron oxidation state or XMe3+ = Me3+/(Me2+ + Me3+) for this remarkable group of zirconolites, where X-REE* is derived from X-REE = REE/(REE + Ca) and XMe5+* from XMe5+ = Me5+/(Me5+ + Ti). Understanding the oxidation state of iron in zirconolite may be helpful to characterize redox conditions during its crystallization.

Citovat

HAIFLER, Jakub, Radek ŠKODA, Jan FILIP, Alf Olav LARSEN a Jan ROHLÍČEK. Zirconolite from Larvik Plutonic Complex, Norway, its relationship to stefanweissite and nöggerathite, and contribution to the improvement of zirconolite endmember systematics. American Mineralogist. Mineralogical Society of America, 2021, roč. 106, č. 8, s. 1255-1272. ISSN 0003-004X. Dostupné z: https://dx.doi.org/10.2138/am-2021-7510.

@article{1754636,
   author = {Haifler, Jakub and Škoda, Radek and Filip, Jan and Larsen, Alf Olav and Rohlíček, Jan},
   article_number = {8},
   doi = {http://dx.doi.org/10.2138/am-2021-7510},
   keywords = {zirconolite; stefanweissite; nöggerathite; polymignyte; Larvik Plutonic Complex; metamict; endmember; composition space; substitution; Rietveld refinement},
   language = {eng},
   issn = {0003-004X},
   journal = {American Mineralogist},
   title = {Zirconolite from Larvik Plutonic Complex, Norway, its relationship to stefanweissite and nöggerathite, and contribution to the improvement of zirconolite endmember systematics},
   url = {https://doi.org/10.2138/am-2021-7510},
   volume = {106},
   year = {2021}
}

TY  - JOUR
ID  - 1754636
AU  - Haifler, Jakub - Škoda, Radek - Filip, Jan - Larsen, Alf Olav - Rohlíček, Jan
PY  - 2021
TI  - Zirconolite from Larvik Plutonic Complex, Norway, its relationship to stefanweissite and nöggerathite, and contribution to the improvement of zirconolite endmember systematics
JF  - American Mineralogist
VL  - 106
IS  - 8
SP  - 1255-1272
EP  - 1255-1272
PB  - Mineralogical Society of America
SN  - 0003004X
KW  - zirconolite
KW  - stefanweissite
KW  - nöggerathite
KW  - polymignyte
KW  - Larvik Plutonic Complex
KW  - metamict
KW  - endmember
KW  - composition space
KW  - substitution
KW  - Rietveld refinement
UR  - https://doi.org/10.2138/am-2021-7510
N2  - The very first description of zirconolite, originally called polymignyte, discovered in alkaline pegmatites within the Larvik Plutonic Complex (LPC), Norway, was published almost 200 yr ago. We studied zirconolite from three occurrences located in this region using modern techniques-X-ray powder diffraction (XRPD) upon thermal annealing of initially radiation-damaged mineral, electron probe microanalysis, and Mossbauer spectroscopy. The initial XRPD pattern lacked any sharp diffraction maxima, as the accumulated radiation dose exceeded a critical value of ca. 10(16) alpha-decays/mg. Annealing at 400-800 degrees C induced recrystallization to a transitional, cubic phase interpreted to have a disordered, defect fluorite structure [space group Fm (3) over barm; unit-cell parameters: a = 5.1047(4) angstrom, V = 133.02(2) angstrom(3)], with its XRPD pattern being very similar to that of cubic ZrO2. Rietveld analysis of the XRPD pattern obtained after a phase transition at 900 degrees C shows a mixture of -30 [wt. fraction of ca. 60%, space group Cmca, unit-cell parameters: a = 7.2664(8) angstrom, b = 14.1877(15) angstrom, c = 10.1472(12) angstrom, V = 1046.1(2) angstrom(3)], and -3T [wt. fraction of ca. 40%, space group P3(1)21, unit-cell parameters: a = 7.2766(6) angstrom, c = 17.0627(15) angstrom, V = 752.42(11) angstrom(3)] zirconolite polytypes. However, the crystal habits of zirconolite from the LPC show a distinct orthorhombic symmetry. Although their chemical compositions are far from the ideal zirconolite composition and a large number of elements are involved in high concentrations [up to ca. 17 wt% REE2O3, <= 7 wt% ACTO(2), <= 18 wt% Me25+O5, <= 9 wt% Me2-O + Me23+O3, Fe3+/(Fe3++Fe2+) approximate to 0.2, where ACT = Th + U, Me5+ = Nb +/- Ta, Me2+ = Fe2+ +/- Mg, Me3+ approximate to Fe3+], the compositional variability is relatively limited. To quantitatively describe the two distinct compositional trends observed, we introduced a concept called "edgemembers," so that mixing is approximated to occur between two terminal compositions situated at two edges of the zirconolite composition space. These marginal compositions were determined from observed compositional trends, i.e., heterovalent substitution of Me5+ for Ti in octahedral sites and ACT enrichment associated with increasing Ti/Me5+ ratio. This approach provides general substitution vectors for both, Hakestad-type mode (ACT + 3 Ti + Me3+ = Ca + 3 Me5+ + Me2+), and Stalaker-type mode (0.7 ACT + 0.5 REE + 0.9 Ti + 0.7 Me3+ + 0.05 Zr = 1.2 Ca + 1.3 Me5+ + 0.3 Me2(+) + 0.05 Mn). In terms of chemical composition, the studied zirconolite corresponds to recently approved zirconolite-related minerals stefanweissite (for Ca > REE) and noggerathite (for REE > Ca). Based on a careful analysis of zirconolite composition space, we show that our observed HAkestad-type compositional trend, as well as a high number of published zirconolite compositions worldwide (with Me2+ + Me3+ sum of ca. 1 atom per 14 O), can be well approximated by a modified end-member set comprising Ca2Zr2Me25+TiMe2+O14, REE2Zr2Ti3Me2+O14, CaACTZr(2)Ti(3)Me(2+)O(14), CaREEZr2Ti3Me3+O14, Ca2Zr2Ti2Me5+Me5+O14 without a need to involve the ideal zirconolite formula Ca2Zr2Ti4O14. The redefined composition space constrained by end-members from this set, together with ideal zirconolite, may be representative of the vast majority of more than 450 published zirconolite compositions worldwide with Me2++Me3+ totaling <= 1 atom per 14 O. The equation XMe3+ = 2 - 2X(REE*) - 3(XMe)(5)(+*) provides an independent calculation of iron oxidation state or XMe3+ = Me3+/(Me2+ + Me3+) for this remarkable group of zirconolites, where X-REE* is derived from X-REE = REE/(REE + Ca) and XMe5+* from XMe5+ = Me5+/(Me5+ + Ti). Understanding the oxidation state of iron in zirconolite may be helpful to characterize redox conditions during its crystallization.
ER  -

HAIFLER, Jakub, Radek ŠKODA, Jan FILIP, Alf Olav LARSEN a Jan ROHLÍČEK. Zirconolite from Larvik Plutonic Complex, Norway, its relationship to stefanweissite and nöggerathite, and contribution to the improvement of zirconolite endmember systematics. \textit{American Mineralogist}. Mineralogical Society of America, 2021, roč.~106, č.~8, s.~1255-1272. ISSN~0003-004X. Dostupné z: https://dx.doi.org/10.2138/am-2021-7510.

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