Meteorite
dwhe...@ipns.com
not trash, and certainly come under the classification of treasure for
at least some people. One of these would be meteorites.
Meteorites have often large amounts of native iron, may have nickel,
and can even contain olivine. They will certainly cause a metal
detector to sing out from quite a distance away. But did you know that
an iron-nickel meteorite should also attract a sensitive compass? If
you wish to cover a lot of ground in a short period, using a
magnetometer (which measures the earth's magnetic field) will
certainly find variations in the magnetic field. This in compination
with a metal detector, a hand-held compass, and some basic knowledge
of meteorite composition might enable you to find something which is
often sold for hundreds or thousands of dollars per pound.
Most recent meteorites have either a black or dark reddish brown/black
fusion crust on the outer 1-4mm of the stone. A metal file or rasp
should reveal metal under this crust. If you strike a meteorite with a
hammer or rock hammer, it may well ring like a bell. That was one of
the tests used by Ellis Hughes in 1902 when he found the 15 1/2-ton
Willamette Meteorite near West Linn, Oregon.
There are probably thousands of meteorites waiting to be found in the
U.S., if not in every state.
If you find a hot rock, as we old-timers used to call them, it
behooves you to send all or a piece of the stone in for
identification. A small sample is required for this: usually an ounce
or less. Finally, if you find a real iron-nickel meteorite, you may be
hard-put to break off a small piece of identification purposes (this
will be returned to you if you request): many are so dense and hard
that even a sledge hammer will not dent them. I have a small piece of
what is either a meteorite or a piece of space debris, that landed
near the finder about 1976. After he cleaned himself off (if you had
something hit less than 100 feet away traveling at 20-30 miles per
second, you might sh*t yourself too) he discovered a black stone with
snowflakes already on it.
So... who's found a meteorite or thinks they have in this group?
Another interesting feature of some meteorites is the presence of
remaglypts: an odd word that simply describes thumb-like depressions,
often found on meteorites, caused by ablation. Ablation is another odd
word to most people, that merely describes the friction of
progressively denser air as a meteor travels through the Earth's
atmosphere.
Recently, a 4 gram (that's right, gram!) Martian meteorite was sold at
auction for ... $12,000! At that rate, a 1 pound mass would be worth
in the neighborhood of $1.2 million.
Daniel B. Wheeler
JHL
dwhe...@ipns.com
Most of the tests now are not destructive. Much has been advanced in
meteorite detection and identification in the past 15 years. While
most identification labs would like you to contribute a small portion
for their collection, usually samples submitted are not meteoric in
nature.
Positive identification of the majority of meteorites can be done in
the field. 1) dense/heavy for the size of the stone 2) fusion crust on
the outside, usually a milimeter or more in depth 3) some silver
coloration exposed with a file 4) thumbprints (regmaglypts) 5)
irregular shapes
Of course, if you happen to see it fall, it helps too.<G> Or even hear
it fall. Meteorites that fall very close to you may sound give off a
fluttering or hissing sound. You generally would be able to hear the
impact if nearby. If not nearby, the overhead meteorite often leaves a
smoke trail for hundreds of miles, and may produce a sonic boom.
Daniel B. Wheeler
Daniel B. Wheeler
sgt23
>
> - Show quoted text -
As long as I don't get hit in the head with one I'll keep my eyes open
for Them. I had friend find a meteorite about 5 years ago in Arizona.
It was only about the size of a baseball, but was made of nickel from
how described it.
dwhe...@ipns.com
sell for $1500 or more. Especially if the Widmanstatten patterns show
it was a totally new meteorite, and not a piece of a previously known
fall.
It is still essential that all potential meteorites are sliced and
etched. Etching does not destroy the meteorite, but the cutting does
remove a portion, which can vary from a few grams to several pounds
for an extremely large meteorite. Nonetheless, the slicing and etching
will *prove* whether the stone is an actual meteorite or not.
Currently looking for a historic fall (someone witnessed it fall)
estimated to weigh over 2,000 pounds, and possibly more than 1,000 kg.
Have picture and printed story of the fall, but the person who
witnessed the fall has since died. May try finding if family members,
who might still be in the area, have any reminiscences of the finder.
Daniel B. Wheeler
sgt23
I don't know the color or weight, he has never showed me a picture of
it. I only know how he described it and he isn't one to lie about
things. I haven't talked to him in over a year so he might have sold
it or who knows what. I just thought it was cool and would relate to
this thread!
celtex
Dan,
Where you from? Has any 'rites been found in Texas? Sounds like a fun
undertaking if you don't mind walking forever LOL
Jim
dwhe...@ipns.com
Have .,.. any meteorites been found in Texas? Sure, loads. Why would
you walk forever? I'm confused. Micrometeorites are quite common and
found after many rains. Visible meteorites are probably in every
square mile of the United States and the oceans. While reading about
the recovery of the Nuestra Senora de Atocha, Mel Fischer said the
exploratory ships he sent out were constantly finding old bombs, old
lost mines (that go boom), lobster pots, and yes, meteorites. I wonder
if Fischer knew the value of meteorites, whether he wouldn't have
recovered a few more of them.
BTW, a good compass and small magnet are probably as important to
identifying meteorites as a metal detector. The impact of an iron or
nickel-iron meteorite should instantly change them into a magnet. If
they have sufficient mass, they would vary the magnetic field of the
earth near them. How near you would have to be to determine that field
depends on how large the meteorite is. Try taking a compass and a
magnet to a local museum that has a meteorite, and seeing how quickly
you could detect them.
Daniel B. Wheeler
kathy1945
metal detector from the scrapyard. I was in the usual coin-shooting
areas, wasn't finding anything but junk, and people were poking fun at
me. I really liked the hobby, and I'm a rock collector from way
back. I don't know why I didn't think of meteorite detecting before.
I was lucky enough to see the huge pallasite meteor in Greensburg, KS
before it got whacked by that tornado. I must say it looked just like
a ..... uh .... rock. So how do you go about finding the meteorites
to even test? I'm in western TN. Do you know if that's a good
meteorite area? Are there any online clubs or resources devoted
exclusively to this topic. I can only find very general info. Thanks
again for posting.
dwhe...@ipns.com
Lots of info available on the web, Kathy. A lot of physical
characteristics which can be done in the field. Carry a small compass,
a magnet, and a file (even a sledge hammer won't dent most
meteorites). By the way, nearly half of all meteorites will ring like
a bell when hit with a rock or hammer (sometimes even your fist).
TN should have lots of meteorites - just like every other state in the
US. There is no magic location for finding meteorites. But if you live
near a desert area, or sand dunes, or flat fields, it can be much
easier. Someone has stated that the tool that fnds more meteorites
than any other is the plow!
Daniel B. Wheeler
kathy1945
"...if you live near a desert area, or sand dunes, or flat fields, it
can be much
> easier. Someone has stated that the tool that fnds more meteorites
> than any other is the plow!"
Thanks, Daniel. Will check web resources as you suggest. Should have
a very successful
meteoritist career - we have a lot of fields and plows here.