R050203 - RRUFF Database: Raman, X-ray, Infrared, and Chemistry

Zircon R050203

Name: Zircon
RRUFF ID: R050203
Ideal Chemistry: Zr(SiO₄)
Locality: Eastern Thailand
Source: Eric Van Valkenburg
Owner: RRUFF
Description: Dark red water-worn single crystal
Status: The identification of this mineral has been confirmed by X-ray diffraction and chemical analysis

Mineral Group: [ Zircon (35) ]

Quick search: [ All Zircon samples (17) ]

CHEMISTRY

RRUFF ID:	R050203.2
Sample Description:	Microprobe Fragment
Measured Chemistry:	(Zr_0.99Hf_0.01)_Σ=1Si_1.00O₄
Microprobe Data File:	[ Download Excel File ]

RAMAN SPECTRUM

RRUFF ID:

Sample Description:

Sample is oriented, mounted on a pin and polished.

Pin ID:

L01102

Orientation:

Laser parallel to c* (0 0 1). Fiducial mark perpendicular to laser is parallel to a [1 0 0].

DOWNLOADS:

To download sample data,
please select a specific
orientation angle.

Raman Mode Analysis

BROAD SCAN WITH SPECTRAL ARTIFACTS

RRUFF ID:

R050203

Wavelength:

Sample Description:

Unoriented sample, 780 nm Raman overwhelmed by fluorescence

Instrument settings:

Thermo Almega XR 532nm @ 100% of 150mW

DOWNLOADS:

	Raman Data (Processed)
	RRUFF File
	Raman Data (RAW)
	RRUFF File

INFRARED SPECTRUM (Attenuated Total Reflectance)

RRUFF ID:

R050203.1

Sample Description:

Powder

Instrument settings:

SensIR Durascope on a Nicolet Magna 860 FTIR

Resolution:

DOWNLOADS:

	Infrared Data (Processed)
	RRUFF File

RRUFF ID:

R050203.1

Sample Description:

Powder

Instrument settings:

PIKE GladiATR - Far-IR on a Nicolet Magna 860 FTIR

Resolution:

DOWNLOADS:

	Infrared Data (Processed)
	RRUFF File

POWDER DIFFRACTION

RRUFF ID:

R050203.1

Sample Description:

Powder

Cell Refinement Output:

a: 6.6049(1)Å b: 6.6049(1)Å c: 5.9801(2)Å
alpha: 90.° beta: 90.° gamma: 90.° Volume: 260.88(1)Å³ Crystal System: tetragonal

File Type Information

Calculated diffraction file.

File Type Information

Output file from the Bruker D8 Advance instrument. Includes device headers and XY data.

File Type Information

Output file from the Bruker D8 Advance instrument. Includes device headers and XY data.

DOWNLOADS:

	Cell Refinement Data
	Cell Refinement Output Data
	DIF File
	X-ray Data (XY - Processed)
	RRUFF File
	X-ray Data (XY - RAW)
	RRUFF File

REFERENCES for Zircon
American Mineralogist Crystal Structure Database Record: [view record]
Anthony J W, Bideaux R A, Bladh K W, and Nichols M C (1990) Handbook of Mineralogy, Mineral Data Publishing, Tucson Arizona, USA, by permission of the Mineralogical Society of America. [view file]
Bras-de-Fer L (1778) (84) Terre (Élément), in Explication Morale du Jeu de Cartes; Anecdote Curieuse et Interessante Bruxelles 99-100 [view file]
Rome de l´Isle J B L (1783) Genre VII. Cristaux-Gemmes. Espèce III. Rubis spinelle octaèdre, in Cristallographie, Volume 2, 2nd Edition De L´Imprimerie de Monsieur Paris 224-230 [view file]
Kirwan R (1794) Seventh genus. Jargon. Zircon of the Germans, in Elements of Mineralogy, 2nd Edition, Volume 1 Elmsly London 333-334 [view file]
Hutton C O (1950) Studies of heavy detrital minerals, Bulletin of the Geological Society of America, 61, 635-710 [view file]
Nicola J H, Rutt H N (1974) A comparative study of zircon (ZrSiO₄) and hafnon (HfSiO₄) Raman spectra, Journal of Physics C: Solid State Physics, 7, 1381-1386
Hazen R M, Finger L W (1979) Crystal structure and compressibility of zircon at high pressure, American Mineralogist, 64, 196-201 [view file]
Černý P, Siivola J (1980) The Tanco pegmatite at Bernic Lake, Manitoba XII. Hafnian zircon, The Canadian Mineralogist, 18, 313-321 [view file]
Kisi E H, Howard C J, Hill R J (1989) Crystal structure of orthorhombic zirconia in partially stabilized zirconia, Journal of the American Ceramic Society, 72, 1757-1760
Armstrong R A, Compston W, Wit M J, Williams I S (1990) The stratigraphy of the 3.5-3.2 Ga Barberton Greenstone Belt revisited: a single zircon ion microprobe study, Earth and Planetary Science Letters, 101, 90-106
Arndt N T, Nelson D R, Compston W, Trendall A F, Thorne A M (1991) The age of the Fortescue Group, Hamersley Basin, Western Australia, from ion microprobe zircon U-Pb results, Australian Journal of Earth Sciences, 38, 261-281
Halden N M, Hawthorne F C, Campbell J L, Teesdale W J, Maxwell J A, Higuchi D (1993) Chemical characterization of oscillatory zoning and overgrowths in zircon using 3 MeV μ-PIXE, The Canadian Mineralogist, 31, 637-647 [view file]
Pinckston R D, Smith D G W (1994) Mineralogy of the Lake zone, Thor Lake rare-metals deposit, N.W.T., Canada, Canadian Journal of Earth Sciences, 32, 516-532
Hoskin P W O, Rodgers K A (1996) Raman spectral shift in the isomorphous series (Zr_1-xHf_x)SiO₄, European Journal of Solid State and Inorganic Chemistry, 33, 1111-1121
Wang R C, Fontan F, Xu S J, Chen X M (1996) Hafnian zircon from the apical part of the Suzhou granite, China, The Canadian Mineralogist, 34, 1001-1010 [view file]
Pan Y (1997) Zircon- and monazite-forming metamorphic reactions at Manitouwadge, Ontario, The Canadian Mineralogist, 35, 105-118 [view file]
Finch R J, Hanchar J M, Hoskin P W O, Burns P C (2001) Rare-earth elements in synthetic zircon: Part 2. A single-crystal X-ray study of xenotime substitution, American Mineralogist, 86, 681-689 [view file]
Kolesov B A, Geiger C A, Armbruster T (2001) The dynamic properties of zircon studied by single-crystal X-ray diffraction and Raman spectroscopy, European Journal of Mineralogy, 13, 939-948
Nasdala L, Wenzel M, Vavra G, Irmer G, Wenzel T, Kober B (2001) Metamictisation of natural zircon: accumulation versus thermal annealing of radioactivity-induced damage, Contributions to Mineralogy and Petrology, 141, 125-144
Moelo Y, Lulzac Y, Rouer O, Palvadeau, Gloaguen E, Léone P (2002) Scandium mineralogy: pretulite with scandian zircon and xenotime-(Y) within an apatite-rich oolitic ironstone from Saint-Aubin-des-Chåteaux, Armorican Massif, France, The Canadian Mineralogist, 40, 1657-1673 [view file]
Shannon R D, Shannon R C, Medenbach O, Fischer R X (2002) Refractive index and dispersion of fluorides and oxides, Journal of Physical and Chemical Reference Data, 31, 931-970 [view file]
Nasdala L, Zhang M, Kempe U, Panczer G, Gaft M, Andrut M, Plötze M (2003) Spectroscopic methods applied to zircon, Reviews in Mineralogy and Geochemistry, 53, 427-467
Gucsik A, Zhang M, Koeberl C, Salje E K H, Redfern S A T, Pruneda J M (2004) Infrared and Raman spectra of ZrSiO₄ experimentally shocked at high pressures, Mineralogical Magazine, 68, 801-811 [view file]
Titorenkova R, Mihailova B, Konstantinov L (2006) Raman spectroscopic study of variably recrystallized metamict zircon from amphibolite-facies metagranites, Serbo-Macedonian massif, Bulgaria, The Canadian Mineralogist, 44, 1357-1366 [view file]
Wittmann A, Kenkmann T, Schmitt R T, Stöffler D (2006) Shock-metamorphosed zircon in terrestrial impact craters, Meteoritics and Planetary Science, 41, 433-454 [view file]
Soba C P, Villaseca C, González Del Tánago J, and Nasdala L (2007) The composition of zircon in the peraluminous Hercynian granites of the Spanish Central System batholith, The Canadian Mineralogist, 45, 509-527 [view file]
Solgadi F, Moyen J F, Vanderhaeghe O, Sawyer E W, Reisberg L (2007) The role of crustal anatexis and mantle-derived magmas in the genesis of synorogenic Hercynian granites of the Livradois area, French Massif Central, The Canadian Mineralogist, 45, 581-606 [view file]
Glass B P, Fries M (2008) Micro-Raman spectroscopic study of fine-grained, shock-metamorphosed rock fragments from the Australasian microtektite layer, Meteoritics and Planetary Science, 43, 1487-1496 [view file]
Marsellos A E, Garver J I (2010) Radiation damage and uranium concentration in zircon as assessed by Raman spectroscopy and neutron irradiation, American Mineralogist, 95, 1192-1201 [view file]
Bačík P, Uher P, Ertl A, Jonsson E, Nysten P, Kanický V, Vaculovič T (2012) Zoned REE-enriched dravite from a granitic pegmatite in Forshammar Bergslagen Province, Sweden: An EMPA, XRD and LA-ICP-MS study, The Canadian Mineralogist, 50, 825-841 [view file]
Schmidt C, Steele-MacInnis M, Watenphul A, Wilke M (2013) Calibration of zircon as a Raman spectroscopic pressure sensor to high temperatures and application to water-silicate melt systems, American Mineralogist, 98, 643-650
McNeil A G, Linnen R L, Flemming R L (2015) Hydrothermal synthesis of columbite-(Mn), tantalite-(Mn), hafnon, and zircon at 800-850°C and 200MPa, The Canadian Mineralogist, 53, 1073-1081
Sutherland F L, Coenraads R R, Abduriyim A, Meffre S, Hoskin P W O, Giuliani G, Beattie R, Wuhrer R, Sutherland G B (2015) Corundum (sapphire) and zircon relationships, Lava Plains gem fields, NE Australia: integrated mineralogy, geochemistry, age determination, genesis and geographical typing, Mineralogical Magazine, 79, 545-581
Breiter K, Müller A, Shail R, Simons B (2016) Composition of zircons from the Cornubian Batholith of SW England and comparison with zircons from other European Variscan rare-metal granites, Mineralogical Magazine, 80, 1273-1289
Grüneberger A M, Schmidt C, Jahn S, Rhede D, Loges A, Wilke M (2016) Interpretation of Raman spectra of the zircon–hafnon solid solution, European Journal of Mineralogy, 28, 721-733
Kempe U, Trinkler M, Pöpple A, Himcinschi (2016) Coloration of natural zircon, The Canadian Mineralogist, 54, 635-660
Wong J, Verdel C, Allen C M (2017) Trace-element compositions of sapphire and ruby from the eastern Australian gemstone belt, Mineralogical Magazine, 81, 1551-1576
Zeng L, Niu H, Bao Z, Yang W (2017) Chemical lattice expansion of natural zircon during the magmatic-hydrothermal evolution of A-type granite, American Mineralogist, 102, 655-665
Capitani G, Mugnaioli E, Gentile P (2018) Submicrometer yttrian zircon coating and arborescent aeschynite microcrystals on truncated bipyramidal anatase: An electron microscopy study of miarolitic cavities in the Cuasso al Monte granophyre (Varese, Italy), American Mineralogist, 103, 480-488
Melnik O E, Bindeman I N (2018) Modeling of trace elemental zoning patterns in accessory minerals with emphasis on the origin of micrometer-scale oscillatory zoning in zircon, American Mineralogist, 103, 355-368
Turner D J, Rivard B, Groat L A (2018) Visible and short-wave infrared reflectance spectoscopy of selected REE-bearing silicate minerals, American Mineralogist, 103, 927-943
Stangarone C, Angel R J, Prencipe M, Campomenosi N, Mihailova B, Alvaro M (2019) Measurement of strains in zircon inclusions by Raman spectroscopy, European Journal of Mineralogy, 31, 685-694
Stangarone C, Angel R J, Prencipe M , Mihailova B , Alvaro M (2019) New insights into the zircon-reidite phase transition, American Mineralogist, 104, 830-837
Tokuda M, Yoshiasa A, Kojitani H, Hashimoto S, Uehara S, Mashimo T, Tobase T, Akaogi M (2019) The importance of cation–cation repulsion in the zircon–reidite phase transition and radiation-damaged zircon, Mineralogical Magazine, 83, 561-567
Borst A M, Finch A A, Friis H, Horsburgh N J, Gamaletsos P N, Goettlicher J, Steininger R, Geraki K (2020) Structural state of rare earth elements in eudialyte-group minerals, Mineralogical Magazine, 84, 19-34
Campomenosi N, Rubatto D, Hermann J, Mihailova B, Scambelluri M, Alvaro M (2020) Establishing a protocol for the selection of zircon inclusions in garnet for Raman thermobarometry, American Mineralogist, 105, 992-1001
Rezvukhina O V, Korsakov A V, Rezvukhin D I, Mikhailenko D S, Zamyatin D A, Greshnyakov E D, Shur V Y (2020) Zircon from diamondiferous kyanite gneisses of the Kokchetav massif: Revealing growth stages using an integrated cathodoluminescence, Raman spectroscopy and electron microprobe approach, Mineralogical Magazine, 84, 949-958 [view file]
Yang C M, Xu Y G, Xia X P, Gao Y Y, Zhang W F, Yang Y N, Yang Q, Zhang L (2022) Raman spectroscopy-based screening of zircon for reliable water content and oxygen isotope measurements, American Mineralogist, 107, 936-945

REFERENCES for Zircon

American Mineralogist Crystal Structure Database Record: [view record]

Anthony J W, Bideaux R A, Bladh K W, and Nichols M C (1990) Handbook of Mineralogy, Mineral Data Publishing, Tucson Arizona, USA, by permission of the Mineralogical Society of America. [view file]

Bras-de-Fer L (1778) (84) Terre (Élément), in Explication Morale du Jeu de Cartes; Anecdote Curieuse et Interessante Bruxelles 99-100 [view file]

Rome de l´Isle J B L (1783) Genre VII. Cristaux-Gemmes. Espèce III. Rubis spinelle octaèdre, in Cristallographie, Volume 2, 2nd Edition De L´Imprimerie de Monsieur Paris 224-230 [view file]

Kirwan R (1794) Seventh genus. Jargon. Zircon of the Germans, in Elements of Mineralogy, 2nd Edition, Volume 1 Elmsly London 333-334 [view file]

Hutton C O (1950) Studies of heavy detrital minerals, Bulletin of the Geological Society of America, 61, 635-710 [view file]

Nicola J H, Rutt H N (1974) A comparative study of zircon (ZrSiO₄) and hafnon (HfSiO₄) Raman spectra, Journal of Physics C: Solid State Physics, 7, 1381-1386

Hazen R M, Finger L W (1979) Crystal structure and compressibility of zircon at high pressure, American Mineralogist, 64, 196-201 [view file]

Černý P, Siivola J (1980) The Tanco pegmatite at Bernic Lake, Manitoba XII. Hafnian zircon, The Canadian Mineralogist, 18, 313-321 [view file]

Kisi E H, Howard C J, Hill R J (1989) Crystal structure of orthorhombic zirconia in partially stabilized zirconia, Journal of the American Ceramic Society, 72, 1757-1760

Armstrong R A, Compston W, Wit M J, Williams I S (1990) The stratigraphy of the 3.5-3.2 Ga Barberton Greenstone Belt revisited: a single zircon ion microprobe study, Earth and Planetary Science Letters, 101, 90-106

Arndt N T, Nelson D R, Compston W, Trendall A F, Thorne A M (1991) The age of the Fortescue Group, Hamersley Basin, Western Australia, from ion microprobe zircon U-Pb results, Australian Journal of Earth Sciences, 38, 261-281

Halden N M, Hawthorne F C, Campbell J L, Teesdale W J, Maxwell J A, Higuchi D (1993) Chemical characterization of oscillatory zoning and overgrowths in zircon using 3 MeV μ-PIXE, The Canadian Mineralogist, 31, 637-647 [view file]

Pinckston R D, Smith D G W (1994) Mineralogy of the Lake zone, Thor Lake rare-metals deposit, N.W.T., Canada, Canadian Journal of Earth Sciences, 32, 516-532

Hoskin P W O, Rodgers K A (1996) Raman spectral shift in the isomorphous series (Zr_1-xHf_x)SiO₄, European Journal of Solid State and Inorganic Chemistry, 33, 1111-1121

Wang R C, Fontan F, Xu S J, Chen X M (1996) Hafnian zircon from the apical part of the Suzhou granite, China, The Canadian Mineralogist, 34, 1001-1010 [view file]

Pan Y (1997) Zircon- and monazite-forming metamorphic reactions at Manitouwadge, Ontario, The Canadian Mineralogist, 35, 105-118 [view file]

Finch R J, Hanchar J M, Hoskin P W O, Burns P C (2001) Rare-earth elements in synthetic zircon: Part 2. A single-crystal X-ray study of xenotime substitution, American Mineralogist, 86, 681-689 [view file]

Kolesov B A, Geiger C A, Armbruster T (2001) The dynamic properties of zircon studied by single-crystal X-ray diffraction and Raman spectroscopy, European Journal of Mineralogy, 13, 939-948

Nasdala L, Wenzel M, Vavra G, Irmer G, Wenzel T, Kober B (2001) Metamictisation of natural zircon: accumulation versus thermal annealing of radioactivity-induced damage, Contributions to Mineralogy and Petrology, 141, 125-144

Moelo Y, Lulzac Y, Rouer O, Palvadeau, Gloaguen E, Léone P (2002) Scandium mineralogy: pretulite with scandian zircon and xenotime-(Y) within an apatite-rich oolitic ironstone from Saint-Aubin-des-Chåteaux, Armorican Massif, France, The Canadian Mineralogist, 40, 1657-1673 [view file]

Shannon R D, Shannon R C, Medenbach O, Fischer R X (2002) Refractive index and dispersion of fluorides and oxides, Journal of Physical and Chemical Reference Data, 31, 931-970 [view file]

Nasdala L, Zhang M, Kempe U, Panczer G, Gaft M, Andrut M, Plötze M (2003) Spectroscopic methods applied to zircon, Reviews in Mineralogy and Geochemistry, 53, 427-467

Gucsik A, Zhang M, Koeberl C, Salje E K H, Redfern S A T, Pruneda J M (2004) Infrared and Raman spectra of ZrSiO₄ experimentally shocked at high pressures, Mineralogical Magazine, 68, 801-811 [view file]

Titorenkova R, Mihailova B, Konstantinov L (2006) Raman spectroscopic study of variably recrystallized metamict zircon from amphibolite-facies metagranites, Serbo-Macedonian massif, Bulgaria, The Canadian Mineralogist, 44, 1357-1366 [view file]

Wittmann A, Kenkmann T, Schmitt R T, Stöffler D (2006) Shock-metamorphosed zircon in terrestrial impact craters, Meteoritics and Planetary Science, 41, 433-454 [view file]

Soba C P, Villaseca C, González Del Tánago J, and Nasdala L (2007) The composition of zircon in the peraluminous Hercynian granites of the Spanish Central System batholith, The Canadian Mineralogist, 45, 509-527 [view file]

Solgadi F, Moyen J F, Vanderhaeghe O, Sawyer E W, Reisberg L (2007) The role of crustal anatexis and mantle-derived magmas in the genesis of synorogenic Hercynian granites of the Livradois area, French Massif Central, The Canadian Mineralogist, 45, 581-606 [view file]

Glass B P, Fries M (2008) Micro-Raman spectroscopic study of fine-grained, shock-metamorphosed rock fragments from the Australasian microtektite layer, Meteoritics and Planetary Science, 43, 1487-1496 [view file]

Marsellos A E, Garver J I (2010) Radiation damage and uranium concentration in zircon as assessed by Raman spectroscopy and neutron irradiation, American Mineralogist, 95, 1192-1201 [view file]

Bačík P, Uher P, Ertl A, Jonsson E, Nysten P, Kanický V, Vaculovič T (2012) Zoned REE-enriched dravite from a granitic pegmatite in Forshammar Bergslagen Province, Sweden: An EMPA, XRD and LA-ICP-MS study, The Canadian Mineralogist, 50, 825-841 [view file]

Schmidt C, Steele-MacInnis M, Watenphul A, Wilke M (2013) Calibration of zircon as a Raman spectroscopic pressure sensor to high temperatures and application to water-silicate melt systems, American Mineralogist, 98, 643-650

McNeil A G, Linnen R L, Flemming R L (2015) Hydrothermal synthesis of columbite-(Mn), tantalite-(Mn), hafnon, and zircon at 800-850°C and 200MPa, The Canadian Mineralogist, 53, 1073-1081

Sutherland F L, Coenraads R R, Abduriyim A, Meffre S, Hoskin P W O, Giuliani G, Beattie R, Wuhrer R, Sutherland G B (2015) Corundum (sapphire) and zircon relationships, Lava Plains gem fields, NE Australia: integrated mineralogy, geochemistry, age determination, genesis and geographical typing, Mineralogical Magazine, 79, 545-581

Breiter K, Müller A, Shail R, Simons B (2016) Composition of zircons from the Cornubian Batholith of SW England and comparison with zircons from other European Variscan rare-metal granites, Mineralogical Magazine, 80, 1273-1289

Grüneberger A M, Schmidt C, Jahn S, Rhede D, Loges A, Wilke M (2016) Interpretation of Raman spectra of the zircon–hafnon solid solution, European Journal of Mineralogy, 28, 721-733

Kempe U, Trinkler M, Pöpple A, Himcinschi (2016) Coloration of natural zircon, The Canadian Mineralogist, 54, 635-660

Wong J, Verdel C, Allen C M (2017) Trace-element compositions of sapphire and ruby from the eastern Australian gemstone belt, Mineralogical Magazine, 81, 1551-1576

Zeng L, Niu H, Bao Z, Yang W (2017) Chemical lattice expansion of natural zircon during the magmatic-hydrothermal evolution of A-type granite, American Mineralogist, 102, 655-665

Capitani G, Mugnaioli E, Gentile P (2018) Submicrometer yttrian zircon coating and arborescent aeschynite microcrystals on truncated bipyramidal anatase: An electron microscopy study of miarolitic cavities in the Cuasso al Monte granophyre (Varese, Italy), American Mineralogist, 103, 480-488

Melnik O E, Bindeman I N (2018) Modeling of trace elemental zoning patterns in accessory minerals with emphasis on the origin of micrometer-scale oscillatory zoning in zircon, American Mineralogist, 103, 355-368

Turner D J, Rivard B, Groat L A (2018) Visible and short-wave infrared reflectance spectoscopy of selected REE-bearing silicate minerals, American Mineralogist, 103, 927-943

Stangarone C, Angel R J, Prencipe M, Campomenosi N, Mihailova B, Alvaro M (2019) Measurement of strains in zircon inclusions by Raman spectroscopy, European Journal of Mineralogy, 31, 685-694

Stangarone C, Angel R J, Prencipe M , Mihailova B , Alvaro M (2019) New insights into the zircon-reidite phase transition, American Mineralogist, 104, 830-837

Tokuda M, Yoshiasa A, Kojitani H, Hashimoto S, Uehara S, Mashimo T, Tobase T, Akaogi M (2019) The importance of cation–cation repulsion in the zircon–reidite phase transition and radiation-damaged zircon, Mineralogical Magazine, 83, 561-567

Borst A M, Finch A A, Friis H, Horsburgh N J, Gamaletsos P N, Goettlicher J, Steininger R, Geraki K (2020) Structural state of rare earth elements in eudialyte-group minerals, Mineralogical Magazine, 84, 19-34

Campomenosi N, Rubatto D, Hermann J, Mihailova B, Scambelluri M, Alvaro M (2020) Establishing a protocol for the selection of zircon inclusions in garnet for Raman thermobarometry, American Mineralogist, 105, 992-1001

Rezvukhina O V, Korsakov A V, Rezvukhin D I, Mikhailenko D S, Zamyatin D A, Greshnyakov E D, Shur V Y (2020) Zircon from diamondiferous kyanite gneisses of the Kokchetav massif: Revealing growth stages using an integrated cathodoluminescence, Raman spectroscopy and electron microprobe approach, Mineralogical Magazine, 84, 949-958 [view file]

Yang C M, Xu Y G, Xia X P, Gao Y Y, Zhang W F, Yang Y N, Yang Q, Zhang L (2022) Raman spectroscopy-based screening of zircon for reliable water content and oxygen isotope measurements, American Mineralogist, 107, 936-945