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Re: (meteorobs) meteorite or ????

>There has been no comment on my friends find, described in
>the meteorobs-digest vol.3, no. 27 (last item).
>
>Is there really no one out there who has studied or collected meteorites?
>
>If anyone has any comment, I would be most grateful!
-------------------
>While clearing some more of my land here I have found what may possibly be a
>meteorite....and would like to try and verify or dis-prove..
>
>I have very limited rock knowledge, but this piece is certainly NOT from
>around these parts...we are on clay with a chalk base, on a valley top,
>valley base 200 metres down the hill, is river deposits...dot it was found
>found slightly buried, but mostly on surface, of a steep slope...
-------------------

Sorry for the lack of comment.   I am new and figured that other people
would have responded.  The biggest identifer of a meteorite is the high
concentration of iron since most of the stuff on the surface has either
melted to the core of the Earth or is rust.  Country rock doesn't have as
much.  Typically, your near-by universities can identify them for you.
Specifically, I know the U of Arizona, U of Arkansas, and the Smithsonian
Inst will identify them *free*.

I am very interested in meteorites and actually have bought a few pieces.
There are 3 major categories, stony, stony-iron, and iron.  These can be
broken down much more, but I won't go into that here.  You probably found a
stony-iron since it is not pure metal, but it doesn't have chrondules.
There should be a fusion crust on it which sound like what you are
describing.  The shape isn't as important, but it can help.  A bullet shape
does happen, however, it isn't required.  Many have irregular shapes.

Two good books on meteorites are:

Rocks from Space
	by O. Richard Norton, Mountain Press Publishing Co, ISBN 0-87842-302-8
	There is a new edition out, but I don't have it.
	It is very good and complete.  If you read one book on meteorites,
	read this one.

Meteorites and Their Parent Planets
	McSween Harry, Y.  1996, Cambridge University Press
	ISBN 0-521-32431-9.
	Dr. McSween at the U of Tenn, does a lot of work with asteroids and
	meteorites including simulations of formation (which I am
	working on too)
	This book is very technical, with a cosomochemical look.
	You don't need a background in the field to understand it, but
	it is beyond the depth of most people's interest


Ah, I found it!  Dr. Sears from the U of Arkansas gave me a book he wrote
on Meteorites of Arkansas, "Thunderstones."  It has a page on "How to
Recognize a Meteorite".  This is taken verbatim from his book (hope he
doesn't mind)

------------------------
     "Most meteorites are heavier than common terrestrial rocks.  The stony
meteorites are about one and a half times as heavy, while stony-iron and
iron meteorites are considerably heavier.  Meteorites are generally
irregular in shape, but with rounded edges.  Freshly fallen meteorites are
black in color with textures on the surface caused by the flow of molten
material during atmospheric passage.  However, such freshly fallen
meteorites are rare and found usually only after the fall itself has been
witnessed.  Usually, the meteorite has become brown due to weathering and
sometimes may reveal a surface scale.  Meteorites are always compact, not
porous or hollow.  The photographs in Figs 1a, 4, 5, 9 and 17 give some
idea of the external appearance of meteorites.  A good test of authenticity
is to grind a suspected meteorite on an abrasive wheel.  All but a few
meteorites contain grains of metal that appear as shining flecks on the
abraded surface, or they are made almost entirely of metal, in which case
the whole surface appears shiny.  Most meteorites are magnet to some extent.
     "Most major museums, including the University of Arkansas Museum, have
personnel capable of recognizing a meteorite and are happy to make an
identification free of charge.  Send a sample to the museum, with a
description of the circumstances of its find."
------------------------

You can contact Dr. Sears at mailto:cosmo@uafsysb.uarkdot edu
He is the head of the Cosmochemistry Group
http://www.uarkdot edu/depts/cosmo/cosmo.htm

Let me know what happens.  For science, every new meteorites is very
valuable.  Plus, you can get some good $$$ depending on what kind of
meteorite it is.  How much does it weigh?  I would like to see some pic's
of it and if you contact Dr. Sears, keep me informed of what he says.

Eric


Eric E. Palmer
eepalmer@attdot net         http://home.attdot net/~eepalmer


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