[meteorite-list] COMPOSITION OF PERUVIAN METEORITE

From: Sterling K. Webb <sterling_k_webb_at_meteoritecentral.com>
Date: Sun, 23 Sep 2007 16:52:45 -0500
Message-ID: <0fd301c7fe2c$13c62f80$a025e146_at_ATARIENGINE>

An analysis of fragments of the Peruvian meteorite carried out
by the Universidad Mayor de San Andres, La Paz, Bolivia,
Faculty of Geological Sciences, by Mario Blanco Cazas, a
downloadable .pdf document. It's in Spanish. There are graphs
and charts of elemental abundances, and analysis by Xray
fluoresence. Here's some samples of the text with pitiful
translations:

http://fcpn.umsa.bo/fcpn/app?service=external/PublicationDownload&sp=227

La muestra se presenta en estado de polvo y fragmentos peque?os.
De modo general el color es gris verdoso de aspecto granular,
algunos fragmentos, que alcanzan un tama?o m?ximo de 0.5 cm,,
son de aspecto totalmente met?lico. La muestra tiene una
susceptibilidad magn?tica muy alta.

The sample presents in a state of dust and small fragments. In a
general way the color is a greenish gray of a granular aspect, some
fragments, which reach a maximum size of 0.5 cm, have completely
the aspect of metal. The sample has a very high magnetic susceptibility.


"No es compatible con rocas que normalmente se encuentranen la
superficie de la Tierra. Estas relaciones podr?a eventualmente
corresponder a materiales que se encontrar?an mucho m?s al
interior de la tierra, es decir podr?a esperarse en materiales del
Manto. Por tanto, es posible suponer que la muestra analizada,
conten?a minerales de tipo "ULTRAB?SICO" o "BASICO"."

"It is not compatible with rocks that normally are on the surface
of the Earth. These relations it might correspond possibly to materials
that would be much more to the interior of the Earth, that is to
say it might be found in materials of Cloak (the Mantle). Therefore,
it is possible to suppose that the analyzed sample, it was containing
minerals of the type ULTRABASIC or BASIC."


[By Xray diffraction, they give:]

MINERALES IDENTIFICADOS:
CUARZO SiO2 (46-1045)*
FOSTERITA FERRICA (Mg,Fe)2 SiO3 (31-795)*
TROILITA - 2H (FeS) (37-477)*
FERROSILITA (Fe,Mg) SiO3 (31-634)*

[Do we even need a translation? Find much troilite in your back yard?]


ELEMENTOS DETECTADOS (ESTIMACI?N DE CONTENIDOS)
MAYORITARIOS (>2%): Fe, Si, Ca, Ni, Mg.
MINORITARIOS (0.1~ 2%): K, Al, Mn, P, Ti, Co.
TRAZAS (<0.1%): Ir, Zn, Na.

ELEMENTS DETECTED (ESTIMATION OF CONTENTS)
MAJORITY (> 2 %): Fe, Si, Ca, Ni, Mg.
MINORITY (0.1 ~ 2 %): K, Al, Mn, P, Ti, Co.
TRACES (<0.1 %): Ir, Zn, Na.

[Find much Iridium in your back yard?]


"La presencia de CUARZO, entre los minerales identificados,
hace pensar que se debe a una CONTAMINACI?N de la muestra
en el momento del impacto."

"The presence of Quartz among the mineral identifications makes
us think it is owing to the terrestrial contamination of the sample at the
moment of impact."



Thanks to Piper Hollier, who passed me this link.


Sterling K. Webb
Received on Sun 23 Sep 2007 05:52:45 PM PDT