Identifying meteorite

I have picked and kicked thousands of river stones over many
prospecting days.

I have a very pocked, heavy river stone, 5 lbs or so which is
unique. It looks “iron-like” (rusty-blackish).

How would I determine if it is a meteorite?

There are several tests for meteorites - none that you can easily do
wit hthe naked eye unless you are an expert.

  1. The nickel content typically falls in a certain range not found
    in earth rocks.

  2. The outside of the rock should show signs on the rock surface
    being melted as it passed through the atmosphere (could be worn off
    after millions of years though.

  3. certain crystal structure that I forget the name of.

Jon Daniels
The Ring Lord Chainmail

saw it in half and etch it with nital. If it shows Widmanstratten
structure you have made your fortune. If it turns black and smelly
when you cut it you have found a lump of slightly oxidised pyrite.

Nick Royall

Peter, Before you do anything with your unidentified item, I suggest
you go to www.meteorlab.com. This is a lab in New England
specializing in identification of meteors. They also have a
laboratory that will test potential meteors and validate them. There
is a looooot of on their site so do yourself a favor and
check it out before cutting or doing anything else to it…you may
save yourself a lot of grief.

Cheers, from
Don in SOFL.

3. certain crystal structure that I forget the name of. 

Widmanstatten patterns are what you are referring to. The form in
certain meteorites (nickel iron type). Easy to see when the
meteorite is polished and etched.

James Binnion
James Binnion Metal Arts

Hi Peter,

Identifying a meteorite through a short description is very
difficult. There are so many different kinds of meteorites that it is
best to have it physically examined to determine its authenticity.
Having said that though, I would recommend getting doing some
research online and seeing what you can find or checking with any
college you may have nearby with a geology department.

Most people are familiar with the nickel-iron meteorites which are
naturally very heavy and usually covered in a layer of oxidation, but
there are other types such as stoney meteorites which are contain
very little metal (if any at all). Often, these will have a layer of
black crust on them called “fusion-crust” where the meteorite was
scorched entering our atmosphere. There are also more exotic
meteorites such as pallasites which contain crystals of olivine
(otherwise known as peridot) inside of a nickel-iron matrix. To see
an truly exceptional example, look up the Esquel meteorite. It is
very beautiful to see!

I realize this certainly doesn’t answer your question, but hopefully
it will give you a starting point. Also, I would highly recommend the
book, “Rocks from Space: Meteorites and Meteorite Hunters (Astronomy)” by O.
Richard Norton (available on Amazon.com)

Erich C. Shoemaker
Erich Christopher Designs, LLC
Granulated Fine Art Jewelry

Thanks for the web site. The rock I have is about 5 lbs and looks
most like the Sikhote-Alin specimens which are for sale. It may just
be iron-rich vesicular lava.

If I slab it and do the nitric acid/methanol test I do not think it
loses too much of its value if it is meteorite. Or does it?

I have 3 small pieces of a possible meteorite that I need to be
analyzed and authenticated. I know one of you is or knows someone
who could do this for me.

Paf Dvorak

Check your local gem & mineral club. They will know someone who
knows and/or collects or deals in meteorites. The clubs also usually
have rock shows with a meteorite vendor or two. Good luck!