A slice of the Esquel pallasite, clearly showing the large olivine crystals suspended in the metal matrix.
Type Stony-iron
Composition Meteoric iron, Silicates
Total known specimens 49 Main group, 4 Eagle Station, 2 Pyroxene grouplet, 38 ungrouped (93 total)

The pallasites are a class of stony–iron meteorite.

Structure and composition

It consists of centimeter-sized olivine crystals of peridot quality in an iron-nickel matrix. Coarser metal areas develop Widmanstätten patterns upon etching. Minor constituents are schreibersite, troilite, chromite, pyroxenes, and phosphates (whitlockite, stanfieldite, farringtonite, and merrillite).[1][2]

Classification and subgroups

Eagle Station, ES group

Using the oxygen isotopic composition, meteoric iron composition and silicate composition pallasites are divided into 4 subgroups:[3][4]


Pallasites were once thought to originate at the core-mantle boundary of differentiated asteroids that were subsequently shattered through impacts. An alternative recent hypothesis is that they are impact-generated mixtures of core and mantle materials.[5]


Krasnojarsk meteorite

A common error is to associate their name with the asteroid 2 Pallas but their actual name is after the German naturalist Peter Pallas (1741–1811), who studied in 1772 a specimen found earlier near Krasnoyarsk in the mountains of Siberia that had a mass of 680 kilograms (1,500 lb).[6] The Krasnoyarsk mass described by Pallas in 1776 was one of the examples used by E.F.F. Chladni in the 1790s to demonstrate the reality of meteorite falls on the Earth, which were at his time considered by most scientists as fairytales. This rock mass was dissimilar to all rocks or ores found in this area (and the large piece could not have been accidentally transported to the find site), but its content of native metal was similar to other finds known from completely different areas.[7]

Pallasite falls

Pallasites are a rare type of meteorite. Only 61 are known to date, including 10 from Antarctica, with four being observed falls.[8][9] The following four falls are in chronological order:

Notable pallasite finds

Imilac full slice

Although pallasites are a rare meteorite type, enough pallasite material is found in museums and meteorite collections and is available for research. This is due to large finds, some of which yielded more than a metric ton. The following are the largest finds:

See also


  1. Buseck, P.R. (1977). "Pallasite meteorites: mineralogy, petrology, and geochemistry". Geochimica et Cosmochimica Acta. 41 (6): 711–740. Bibcode:1977GeCoA..41..711B. doi:10.1016/0016-7037(77)90044-8.
  2. Hsu, W. (2003). "Minor element zoning and trace element geochemistry of pallasites". Meteoritics & Planetary Science. 38 (8): 1217–1241. Bibcode:2003M&PS...38.1217H. doi:10.1111/j.1945-5100.2003.tb00309.x.
  3. O. Richard Norton. The Cambridge encyclopedia of meteorites. Cambridge, Cambridge University Press, 2002. ISBN 0-521-62143-7.
  4. M. K. Weisberg; T. J. McCoy, A. N. Krot (2006). "Systematics and Evaluation of Meteorite Classification". In D. S. Lauretta; H. Y. McSween, Jr. Meteorites and the early solar system II (PDF). Tucson: University of Arizona Press. pp. 19–52. ISBN 978-0816525621. Retrieved 15 December 2012.
  5. Edward R.D. Scott, "Impact Origins for Pallasites," Lunar and Planetary Science XXXVIII, 2007.
  6. P.S.Pallas, Reise durch die verschiedenen Provinzen des russischen Reichs. St.Petersburg 1776
  7. E.F.F.Chladni, Observation on a mass of iron found in Siberia by Professor Pallas, and other masses of the like kind, with some conjectures respecting their connection with certain natural phenomena. Philosophical Magazine and Journal of Science, 1798, vol.2, 1-8.
  8. Meteoritical Bulletin Database
  9. MetBase
  10. Meteorites Japan
  11. Mammoth meteorite unearthed, January 2006 about the October 2005 find
  12. CNN: Unusual meteorite found in Kansas, October 16, 2006.
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