Physics and Chemistry of Minerals

, Volume 40, Issue 7, pp 575–586 | Cite as

Origin of birefringence in andradite from Arizona, Madagascar, and Iran

Original Paper


The crystal structure of four birefringent andradite samples (two from Arizona, one from Madagascar, and one from Iran) was refined with the Rietveld method, space group \(Ia\overline{3} d\), and monochromatic synchrotron high-resolution powder X-ray diffraction (HRPXRD) data. Each sample contains an assemblage of three different cubic phases. From the electron-microprobe (EMPA) results, fine-scale intergrowths in the Arizona-2 and Madagascar samples appear homogeneous with nearly identical compositions of {Ca2.99Mg0.01}Σ3[\({\text{Fe}}_{1.99}^{3 + }\)\({\text{Mn}}_{0.01}^{3 + }\)]Σ2(Si2.95Al0.03\({\text{Fe}}_{0.02}^{3 + }\))Σ3O12, Adr98 (Arizona-2), and Adr97 (Madagascar). Both samples are near-end-member andradite, ideally {Ca3}[\({\text{Fe}}_{2}^{3 + }\)](Si3)O12, so cation ordering in the X, Y, or Z sites is not possible. Because of the large-scale intergrowths, the Arizona-1 and Iran samples contain three different compositions. Arizona-1 has compositions Adr97 (phase-1), Adr93Grs4 (phase-2), and Adr87Grs11 (phase-3). Iran sample has compositions Adr86Uv12 (phase-1), Adr69Uv30 (phase-2), and Adr76Uv22 (phase-3). The crystal structure of the three phases within each sample was modeled quite well as indicated by the Rietveld refinement statistics of reduced χ2 and overall R (F2) values of, respectively, 1.980 and 0.0291 (Arizona-1); 1.091 and 0.0305 (Arizona-2); 1.362 and 0.0231 (Madagascar); and 1.681 and 0.0304 (Iran). The dominant phase for each sample has the following unit-cell parameters (Å) and weight fractions (%): a = 12.06314(1), 51.93(9) (Arizona-1); 12.04889(1), 52.47(1) (Arizona-2); 12.06276(1), 52.21(8) (Madagascar); and 12.05962(2), 63.3(1) (Iran). For these dominant phases, the distances and site occupancy factors (sofs) in terms of neutral atoms at the Ca(X), Fe(Y), and Si(Z) sites are as follows: <Ca–O> = 2.4348, Fe–O = 2.0121(6), Si–O = 1.6508(6) Å; Ca(sof) = 0.955(2), Fe(sof) = 0.930(2), and Si(sof) = 0.917(2) (Arizona-1); <Ca–O> = 2.4288, Fe–O = 2.0148(7), Si–O = 1.6476(7) Å; Ca(sof) = 0.953(2), Fe(sof) = 0.891(2), and Si(sof) = 0.927(2) (Arizona-2); <Ca–O> = 2.4319, Fe–O = 2.0220(6), Si–O = 1.6460(6) Å; Ca(sof) = 0.955(2), Fe(sof) = 0.941(2), and Si(sof) = 0.939(2) (Madagascar); and <Ca–O> = 2.4344, Fe–O = 2.0156(8), Si–O = 1.6468(8) Å; Ca(sof) = 0.928(2), Fe(sof) = 0.908(2), and Si(sof) = 0.932(3) (Iran). The sofs based on the EMPA results are similar to those obtained from the Rietveld refinement. Each phase in the HRPXRD results can be correlated with a specific chemical composition. For example, the Iran sample composition Adr63Uv30 corresponds to phase-3 that has the smallest unit-cell parameter; Adr76Uv22 corresponds to phase-1 that has the intermediate cell value; and Adr86Uv13 corresponds to phase-2 that has the largest unit-cell parameter. The bond distances compare well with those obtained from radii sum. The three different cubic phases in each sample cause strain that arises from the mismatch of the cubic unit-cell parameters and give rise to birefringence.


Andradite Uvarovite Birefringence Three-phase intergrowths Rietveld refinements Synchrotron high-resolution powder X-ray diffraction (HRPXRD) Crystal structure 

Supplementary material

269_2013_594_MOESM1_ESM.txt (11 kb)
Supplementary material 1 (TXT 11 kb)


  1. Adamo I, Gatta GD, Rotitoti N, Diella V, Pavese A (2010) Green andradite stones: gemological and mineralogical characterisation. Eur J Mineral 23:91–100CrossRefGoogle Scholar
  2. Agrosì G, Schingaro E, Pedrazzi G, Scandale E, Scordari R (2002) A crystal chemical insight into sector zoning of a titanian andradite (‘melanite’) crystal. Eur J Mineral 14:785–794CrossRefGoogle Scholar
  3. Akizuki M (1984) Origin of optical variations in grossular-andradite garnet. Am Mineral 66:403–409Google Scholar
  4. Akizuki M (1989) Growth structure and crystal symmetry of grossular garnets from the Jeffrey mine, Asbestos, Quebec, Canada. Am Mineral 74:859–864Google Scholar
  5. Akizuki M, Takéuchi Y, Terada T, Kudoh Y (1998) Sectoral texture of a cubo-dodecahedral garnet in grandite. Neues Jahrbuch für Mineralogie, Monatshefte 12:565–576Google Scholar
  6. Allen FM, Buseck PR (1988) XRD, FTIR, and TEM studies of optically anisotropic grossular garnets. Am Mineral 73:568–584Google Scholar
  7. Amthauer G, Rossman GR (1998) The hydrous component in andradite garnet. Am Mineral 83:835–840Google Scholar
  8. Angel R, Finger LW, Hazen RM, Kanzaki M, Weidner DJ, Liebermann RC, Veblen DR (1989) Structure and twinning of single-crystal MgSiO3 garnet synthesized at 17 GPa and 1800°C. Am Mineral 74:509–512Google Scholar
  9. Antao SM (2013) Three cubic phases intergrown in a birefringent andradite-grossular garnet and their implications. Phys Chem Mineral (Submitted)Google Scholar
  10. Antao SM, Hassan I (2010) A two-phase intergrowth of genthelvite from Mont Saint-Hilaire, Quebec. Can Mineral 48:1217–1223CrossRefGoogle Scholar
  11. Antao SM, Hassan I, Wang J, Lee PL, Toby BH (2008) State-of-the-art high-resolution powder X-ray diffraction (HRPXRD) illustrated with Rietveld structure refinement of quartz, sodalite, tremolite, and meionite. Can Mineral 46:1501–1509CrossRefGoogle Scholar
  12. Armbruster T, Geiger CA (1993) Andradite crystal chemistry, dynamic x-site disorder and structural strain in silicate garnets. Eur J Mineral 5:59–71Google Scholar
  13. Armbruster T, Birrer J, Libowitzky E, Beran A (1998) Crystal chemistry of Ti-bearing andradites. Eur J Mineral 10:907–921Google Scholar
  14. Badar MA, Akizuki M, Hussain S (2010) Optical anomaly in iridescent andradite from the Sierra Madre Mountains, Sonora, Mexico. Can Mineral 48:1195–1203CrossRefGoogle Scholar
  15. Badar MA, Niaz S, Hussain S, Akizuki M (2013) Lamellar texture and optical anomaly in andradite from the Kamaishi mine, Japan. Eur J Mineral 25:53–60CrossRefGoogle Scholar
  16. Baikie T, Schreyer MK, Wong CL, Pramana SS, Klooster WT, Ferraris C, McIntyre GJ, White TJ (2012) A multi-domain gem-grade Brazilian apatite. Am Mineral 97:1574–1581CrossRefGoogle Scholar
  17. Blanc Y, Maisonneuve J (1973) Sur la biréfringence des grenats calciques. Bulletin de la Société Française de Minéralogie et de Cristallographie 96:320–321Google Scholar
  18. Brauns R (1891) Die optischen Anomalien der Kristalle. Preisschr. Jablonowski Ges, LeipzigGoogle Scholar
  19. Brown D, Mason RA (1994) An occurrence of sectored birefringence in almandine from the Gangon terrane, Labrador. Can Mineral 32:105–110Google Scholar
  20. Chakhmouradian AR, McCammon CA (2005) Schorlomite: a discussion of the crystal chemistry, formula, and inter-species boundaries. Phys Chem Miner 32:277–289CrossRefGoogle Scholar
  21. Chase AB, Lefever RA (1960) Birefringence of synthetic garnets. Am Mineral 45:1126–1129Google Scholar
  22. Deer WA, Howie RA, Zussman J (1992) An introduction to the rock-forming minerals, 2nd edn. Wiley, New York, NYGoogle Scholar
  23. Evans BW, Johannes J, Oterdoom H, Trommsdorff V (1976) Stability of chrysotile and antigorite in the serpentinite multisystem. Schweiz Mineral Petrogr Mitt 56:79–93Google Scholar
  24. Foord EE, Mills BA (1978) Biaxiality in ‘isometric’ and ‘dimetric’ crystals. Am Mineral 63:316–325Google Scholar
  25. Frank-Kamenetskaya OV, Rozhdestvenskaya LV, Shtukenberg AG, Bannova II, Skalkina YA (2007) Dissymmetrization of crystal structures of grossular-andradite garnets Ca3(Al, Fe)2(SiO4)3. Struct Chem 18:493–503CrossRefGoogle Scholar
  26. Griffen DT, Hatch DM, Phillips WR, Kulaksiz S (1992) Crystal chemistry and symmetry of a birefringent tetragonal pyralspite75-grandite25 garnet. Am Mineral 77:399–406Google Scholar
  27. Hofmeister AM, Schaal RB, Campbell KR, Berry SL, Fagan TJ (1998) Prevalence and origin of birefringence in 48 garnets from the pyrope-almandine- grossularite-spessartine quaternary. Am Mineral 83:1293–1301Google Scholar
  28. Ingerson E, Barksdale JD (1943) Iridescent garnet from the Adelaide mining district, Nevada. Am Mineral 28:303–312Google Scholar
  29. Jamtveit B (1991) Oscillatory zonation patterns in hydrothermal grossular-andradite garnet: nonlinear dynamics in regions of immiscibility. Am Mineral 76:1319–1327Google Scholar
  30. Kingma KJ, Downs JW (1989) Crystal-structure analysis of a birefringent andradite. Am Mineral 74:1307–1316Google Scholar
  31. Kitamura K, Komatsu H (1978) Optical anisotropy associated with growth striation of yttrium garnet, Y3(Al, Fe)5O12. Kristallographie und Technik 13:811–816CrossRefGoogle Scholar
  32. Lager GA, Armbruster T, Rotella FJ, Rossman GR (1989) OH substitution in garnets: X-ray and neutron diffraction, infrared, and geometric-modeling studies. Am Mineral 74:840–851Google Scholar
  33. Larson AC, Von Dreele RB (2000) General structure analysis system (GSAS). Los Alamos National Laboratory Report (LAUR), Philippines, pp 86–748Google Scholar
  34. Lee PL, Shu D, Ramanathan M, Preissner C, Wang J, Beno MA, Von Dreele RB, Ribaud L, Kurtz C, Antao SM, Jiao X, Toby BH (2008) A twelve-analyzer detector system for high-resolution powder diffraction. J Synchrotron Radiat 15:427–432CrossRefGoogle Scholar
  35. Lessing P, Standish RP (1973) Zoned garnet from Crested Butte, Colorado. Am Mineral 58:840–842Google Scholar
  36. Locock AJ (2008) An excel spreadsheet to recast analyses of garnet into end-member components, and a synopsis of the crystal chemistry of natural silicate garnets. Comput Geosci 34:1769–1780CrossRefGoogle Scholar
  37. Munno R, Rossi G, Tadini C (1980) Crystal chemistry of kimzeyite from Stromboli, Aeolian Islands, Italy. Am Mineral 65:188–191Google Scholar
  38. Nakatsuka A, Yoshiasa A, Yamanaka T, Ito E (1999a) Structure refinement of a birefringent Cr-bearing majorite Mg3(Mg0.34Si0.34Al0.18Cr0.14)2Si3O12. Am Mineral 84:199–202Google Scholar
  39. Nakatsuka A, Yoshiasa A, Yamanaka T, Ohtaka O, Katsura T, Ito E (1999b) Symmetry change of majorite solid-solution in the system Mg3Al2Si3O12-MgSiO3. Am Mineral 84:1135–1143Google Scholar
  40. Novak GA, Gibbs GV (1971) The crystal chemistry of the silicate garnets. Am Mineral 56:1769–1780Google Scholar
  41. Peterson RC, Locock AJ, Luth RW (1995) Positional disorder of oxygen in garnet: the crystal-structure refinement of schorlomite. Can Mineral 33:627–631Google Scholar
  42. Rietveld HM (1969) A profile refinement method for nuclear and magnetic structures. J Appl Crystallogr 2:65–71CrossRefGoogle Scholar
  43. Rossman GR, Aines RD (1986) Spectroscopy of a birefringent grossular from Asbestos, Quebec, Canada. Am Mineral 71:779–780Google Scholar
  44. Rossmanith E, Armbruster T (1995) The intensity of forbidden reflections of pyrope: umweganregung or symmetry reduction. Z Kristallogr 210:645–649CrossRefGoogle Scholar
  45. Schingaro E, Scordari F, Capitanio F, Parodi G, Smith DC, Mottana A (2001) Crystal chemistry of kimzeyite from Anguillara, Mts. Sabatini, Italy. Eur J Mineral 13:749–759CrossRefGoogle Scholar
  46. Shannon RD (1976) Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallogr A A32:751–767CrossRefGoogle Scholar
  47. Sheldrick GM (1997) SHELXL-97-1. Program for crystal structure determination. Institut für Anorg. Chemie, University of Göttingen, Göttingen, GermanyGoogle Scholar
  48. Shtukenberg AG, Punin YO, Frank-Kamenetskaya OV, Kovalev OG, Sokolov PB (2001) On the origin of anomalous birefringence in grandite garnets. Mineral Mag 65:445–459CrossRefGoogle Scholar
  49. Shtukenberg AG, Popov DY, Punin YO (2005) Growth ordering and anomalous birefringence in ugrandite garnets. Mineral Mag 69:537–550CrossRefGoogle Scholar
  50. Takéuchi Y, Haga N, Umizu S, Sato G (1982) The derivative structure of silicate garnets in grandite. Z Kristallogr 158:53–99Google Scholar
  51. Toby BH (2001) EXPGUI, a graphical user interface for GSAS. J Appl Crystallogr 34:210–213CrossRefGoogle Scholar
  52. Wang J, Toby BH, Lee PL, Ribaud L, Antao SM, Kurtz C, Ramanathan M, Von Dreele RB, Beno MA (2008) A dedicated powder diffraction beamline at the advanced photon source: commissioning and early operational results. Rev Sci Instrum 79:085105CrossRefGoogle Scholar
  53. Weber HP, Virgo D, Huggins FE (1975) A neutron-diffraction and 57Fe Mössbauer study of a synthetic Ti-rich garnet. Carnegie Inst Wash Year Book 74:575–579Google Scholar
  54. Wildner M, Andrut M (2001) The crystal chemistry of birefringent natural uvarovites: part II. Single-crystal X-ray structures. Am Mineral 86:1231–1251Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Department of GeoscienceUniversity of CalgaryCalgaryCanada

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