Metal Crystallization in IIE Irons and Their Possible Meteorite Analogues


The metal of IIE irons provides evidence of fractionation in the interiors of an asteroid, but their fine-grained structures are incompatible with their endogenous origin. It was proposed that the metal underwent remelting on the surface of the parent body. Data on the mineragraphy and on the mineral and chemical composition of IIE irons (Elga, Verkhnodniprovsk, Tobychan, Miles, and Watson) indicate that the relatively fine-grained metal structure and anhedral schreibersite grains were probably formed by crystallization from melt. According to the calculated data on the bulk composition of the Elga metal and on the Fe–Ni–P phase diagrams, the crystallization of the first γ-Fe grains began at ~1511°С and ended at ~1060–1100°С with the formation of centimeter-sized polygonal crystals of taenite and anhedral schreibersite grains along their boundaries. The identical composition of the anhedral schreibersite, both along the borders of the taenite grains and on the rims around nonmetallic inclusions, indicates that they were formed simultaneously. Among the four generations of schreibersite, the anhedral schreibersite is distinguished for its high Fe/Ni ratio. It was also noted that the higher the crystallization temperature of schreibersite, the lower its Ni content. Similar metal structures were found in other types of meteorites: in IAB irons and in the metal of some mesosiderites, whose impact-related origin is thought to be the most probable. Hence, the mechanism of formation of IIE irons by means of shock remelting of fractionated metal and mixing with silicate fragments on the surface of the parent body may have also produced other meteorite types.

This is a preview of subscription content, access via your institution.

Fig. 1.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.
Fig. 6.


  1. 1

    A. W. R. Bevan, J. Kinder, and H. J. Axon, “A metallographic study of the iron meteorite Verkhne Dnieprovsk (BM 51183),” Mineral. Mag. 43, 149–154 (1979).

    Article  Google Scholar 

  2. 2

    V. Buchwald and R. S. Clarke, Jr., “The Verkhne Dnieprovk iron meteorite specimens in the Vienna collection and the confusion of Verkhne Dnieprovk with Augustinovka,” Meteoritics 22, 121–135 (1987).

    Article  Google Scholar 

  3. 3

    V. F. Buchwald, Handbook of Iron Meteorites. Their History, Distribution, Composition and Structure, (University of California Press, Berkeley, 1975).

    Google Scholar 

  4. 4

    W. Chai, R. M. German, E. A. Olevsky, X. Wei, R. Jiang, and G. Cui, “Preparation and properties of high strength Fe–Ni–P ternary alloys,” Adv. Engin. Mater. 18, 1889–1896 (2016).

    Article  Google Scholar 

  5. 5

    R. S. Clarke and J. I. Goldstein, “Schreibersite growth and its influence on the metallography of coarse-structured iron meteorites,” Smithsonian Contrib. Earth Sci. 21, 1–81 (1978).

    Google Scholar 

  6. 6

    M. I. D’yakonov, V. Ya. Kharitonov, and A. A. Yavnel, Chemical Composition of Meteorites (Nauka, Moscow, 1979) [in Russian].

    Google Scholar 

  7. 7

    A. S. Doan and J. I. Goldstein, “The ternary phase diagram, Fe–Ni—P,” Metallurg. Trans. 1, 1759–1767 (1970).

    Article  Google Scholar 

  8. 8

    M. Ebihara, Y. Ikeda, M. Prinz, “Petrology and chemistry of the Miles IIE iron II: chemical characteristics of the Miles silicate inclusions,” Antarc. Meteorite Res. 10, 373–388 (1997).

    Google Scholar 

  9. 9

    J. Ganguly, H. Yang, and S. Ghose, “Thermal history of mesosiderites: Quantitative constraints from compositional zoning and Fe–Mg ordering in orthopyroxenes,” Geochim. Cosmochim. Acta 58, 2711–2723 (1994).

    Article  Google Scholar 

  10. 10

    J. Hassanzadeh, A. E. Rubin, and J. T. Wasson, “Compositions of large metal nodules in mesosiderites—Links to iron meteorite group IIIAB and the origin of mesosiderite subgroups,” Geochim. Cosmochim. Acta 54, 3197-3208 (1990).

    Article  Google Scholar 

  11. 11

    B. A. Hofmann S. Lorenzetti, O. Eugster, U. Krahenbuhl, G. Herzog, F. Serefiddin, E. Gnos, M. Eggimann, and J. T. Wasson, “The Twannberg (Switzerland) IIG iron meteorites: mineralogy, chemistry, and CRE ages,” Meteorit. Planet. Sci. 44, 187–199 (2009).

  12. 12

    Y. Ikeda and M. Prinz, “Petrology of silicate inclusions in the Miles IIE iron,” Proc. NIPR Symp. Antarct. Meteorit. 9, 143–173 (1996).

  13. 13

    Y. Ikeda, M. Ebihara, and M. Prinz, “Petrology and chemistry of the Miles IIE iron. Description and petrology of twenty new silicate inclusions,” Antarct. Meteorite Res. 10, 355–372 (1997).

    Google Scholar 

  14. 14

    G. M. Ivanova and I. K. Kuznetsova, “Tobychan iron meteorite,” Meteoritika 35, 47–58.

  15. 15

    Kirby, R. S. P. L. King, R. W. Henley, U. Troitzsch, T. R. Ireland, and M. Turner, “A new hypothesis for the evolution of IIE iron meteorites based on geochronology and petrology of the Miles meteorite,” Lunar Planet. Sci. Conf. 47, 1938 (2016).

  16. 16

    G. Kurat, E. Zinner, M. E. Varela, “Trace element studies of silicate-rich inclusions in the Guin (UNGR) and Kodaikanal (IIE) iron meteorites,” Meteorit. Planet Sci. 42, 1441–1463 (2007).

    Article  Google Scholar 

  17. 17

    C. A. Lorenz, M. A. Nazarov, G. Kurat, and N. N. Kononkova, “Silicate inclusions in a metal nodule of the Budulan mesosiderite: mineralogy and origin,” Meteorit. Planet. Sci. 36, Suppl, A116 (2001).

    Google Scholar 

  18. 18

    B. Luais, “Isotopic fractionation of germanium in iron meteorites: Significance for nebular condensation, core formation and impact processes,” Earth and Planet. Sci. Lett. 262, 21–36 (2007).

    Article  Google Scholar 

  19. 19

    E. Olsen, A. Davis, R. J. Clarke, Jr., L. Schultz, and H. W. Weber, “Watson: A new link in the IIE iron chain,” Meteoritics 29, 200–213 (1994).

    Article  Google Scholar 

  20. 20

    M. I. Petaev, and S. B. Jacobsen, “LA-ICP-MS study of trace elements in the Chaunskij Metal,” Lunar Planet. Sci. Conf., 36, no. 1740 (2005).

  21. 21

    M. I. Petaev, R. S. Clarke, Jr., E. J. Olsen, E. Jarosewich, A. M. Davis, I. M. Steele, M. E. Lipschutz, and V. Raghavan, “The Fe–Ni–P (Iron–Nickel–Phosphorus) System,” Phase Diagr. Ternary Iron Alloys 3, 121–137 (1988).

    Google Scholar 

  22. 22

    A. Ruzicka and M. Hutson, “Comparative petrology of silicates in the Udei Station (IAB) and Miles (IIE) iron meteorites: Implications for the origin of silicate-bearing irons,” Geochim. Cosmochim. Acta 74, 394–434 (2010).

    Article  Google Scholar 

  23. 23

    A. Ruzicka, G. W. Fowler, G. A. Snyder, M. Prinz, J. J. Papike, and L. A. Taylor, “Petrogenesis of silicate inclusions in the Weekeroo Station IIE iron meteorite: differentiation, remelting, and dynamic mixing,” Geochim. Cosmochim. Acta 63, 2123–2143 (1999).

    Article  Google Scholar 

  24. 24

    A. Ruzicka, W. V. Boynton, and J. Ganguly, “Olivine coronas, metamorphism, and the thermal history of the Morristown and Emery mesosiderites,” Geochim. Cosmochem. Acta 58, 2725–2741 (1994).

    Article  Google Scholar 

  25. 25

    E. R. D. Scott and J. T. Wasson, “Chemical classification of iron meteorites. VIII. Groups IC, IIE, IIIF and 97 other irons,” Geochim. Cosmochem. Acta 40, 103–115 (1976).

    Article  Google Scholar 

  26. 26

    S. N. Teplyakova, “Evolution of molten material in iron cores of small planets,” Solar System Res. 45 (6), 515–522 (2011).

    Article  Google Scholar 

  27. 27

    S. N. Teplyakova, M. Humayun, C. A. Lorenz, and M. A. Ivanova, “A Common Parent for IIE iron meteorites and H chondrites,” Lunar and Planet. Sci. Conf. 43, #1130 (2012).

  28. 28

    S. N. Teplyakova, C. A. Lorentz, M. A. Ivanova, N. N. Kononkova, M. O. Anosova, K. M. Ryazantzev, and Yu. A. Kostitzin, “Mineralogy of silicate inclusions in IIE iron meteorite Elga,” Geochem. Int. 56 (1), 1–23 (2018).

    Article  Google Scholar 

  29. 29

    N. Van Roosbroek, C. Hamann, S. McKibbin, A. Greshake, R. Wirth, L. Pittarello, L. Hecht, P. Claeys, and V. Debaille, “Immiscible silicate liquids and phosphoran olivine in Netscaevo IIE silicate: Analogue for planetesimal core–mantle boundaries,” Geochim. Cosmochim. Acta 197, 378–395 (2017).

    Article  Google Scholar 

  30. 30

    M.-S. Wang, R. N. Clayton, T. K. Mayeda, and J. A. Wood, “Chaunskij: The most highly metamorphosed, shock-modified and metal-rich mesosiderite,” Lunar and Planet. Sci. Conf. 24, 1131–1132 (1993).

  31. 31

    J. T. Wasson, “Formation of non-magmatic iron-meteorite group IIE,” Geochim. Cosmochem. Acta 53, 396–416 (2017).

    Article  Google Scholar 

  32. 32

    J. T. Wasson and J. Wang, “A nonmagmatic origin of group-IIE iron meteorites,” Geochim. Cosmochim. Acta 50, 725–732 (1986).

    Article  Google Scholar 

Download references


The authors thank O.I. Yakovlev and M.A. Ivanova for recommendations that helped us to improve the manuscript.

Author information



Corresponding authors

Correspondence to S. N. Teplyakova or C. A. Lorenz.

Additional information

Translated by E. Kurdyukov

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Teplyakova, S.N., Lorenz, C.A. Metal Crystallization in IIE Irons and Their Possible Meteorite Analogues. Geochem. Int. 57, 893–902 (2019).

Download citation


  • iron meteorites
  • IIE
  • Elga
  • schreibersite