[meteorite-list] "R" help

[MexicoDoug at aol.com]

Rumuruti's are expected to be weakly magnetic/possibly magnetized.   
Pyrrhotite is usually weakly magnetic, and 5% is going to be really weakly  magnetic 
though I expect it will now deflect a compass needle...but if you look  at the 
composition of Rumuruti's you can learn a lot.

Oh no Tom don't be hard on Martin just because David Weir only anticipated  
999 out of 1000 of our silly questions!!!  My lazy take on this stone made  
famous by Mike Farmer since as he aptly put it, "they stink like sulfur when he  
cuts them" (Mike's descriptions rival those fabled David New Deals).  That  is 
actually a pretty important comment, since it is that slightly iron  
difficient Iron Sulfide known as pyrrhotite that apparently is the main magnetic  
component of Rumuruti chondrites, which Mike did/does have an awesome specimen  in 
his collection.  Pyrrhotite is what does smell like rotten eggs when  
attacked by nibbling meteoritehounds...

That Iron Sulfide in the Rumuruti  Chondrites is found, at least according to 
the excellent team at  Mineralogisch-Petrographisches Institut and Museum, 
Germany &  Max-Planck-Institut fuer Chemie, Germany, in the form of pyrrhotite 
and is the  main magnetic mineral of Rumuruti was tested.  These ace 
researchers went  on to quantify that Rumuruti itself is composed of 4.4 volume percent  
pyrrhotite.  Mind you, that is probably 5% by weight considering its higher  
denisity.

Meteoritics V. 29, No. 2, pp. 275-286 March 1994
"Mineralogy  and Chemistry of Rumuruti: The First Meteorite Fall of the New R 
Chondrite  Group" by Schulze, H.; Bischoff, A.; Palme, H.; Spettel, B.; 
Dreibus, G.; Otto,  J.

Now, on to your question regarding how magnetic.  Well do you  mean magnetic 
in a Dave Freeman sense?  Because, yes, now that you have  ignited Ramona 
Geraldine Quimby (Beezus's little sister)'s curiosity under the  whole meteorite 
world sticking rare earth magnets powered by the dark side of  the force, 
everybody's Rumuruti's are probably magnetized to saturation.   They can test to 
see if the Rumuruti's pick up iron filings now - and some may  truly have 
magnetized meteorites, and in the process have lost scientific value  just like 
putting one of those bad-ass magnets on specimens from a new cassette  tape 
collection to see if they are magnetic (well, are they?).  The funny  thing is they 
were probably weakly magnetized extraterrestrially  before.

Furthermore, the Pope's, France's and Italy's team comment on the  magnetic 
profile of the Rumuruti's, we can learn from harvesting Google, that  the 
Rumuruti exhibits minimal magnetic anisotropy.  That means God's  original 
recording of preferential magnetization axes recorded somehow in  outerspace since the 
mineral pyrrhotite does orient magnetically should happen,  but it became 
unoriented afterwards.  Note unoriented and oriented are  terms for magnetization 
anisotropy here and not flight markings.  This is  noted by these noble 
researchers and explained that they were probably  "recrystalized" after the 
original formation.  I guess they are suggestion  that the pyrrhotite was heated 
above 350 degrees C which ought to do the  trick.  Unless you take a powerful 
enough magnet and try to reorient it  depending on where you stick the magnet...

It is important to know if you  are dealing with an isotropic magnetic 
material or not when you ask questions  like how magnetic - as results can really 
depend on the orientation of the stone  and if you don't know this you can get 
pooh pooh out of the test if not  careful...

Lunar and Planetary Science XXXVI (2005)
AN IMPACT ORIGIN  FOR THE FOLIATION OF ORDINARY CHONDRITES. 
J. Gattacceca1, P. Rochette, M.  Denise, G. Consolmagno, and L. Folco, 
Université Aix-Marseille III, CEREGE,  BP80, 13545 Aixen-Provence, France, MNHN, 
Paris, France, Specola Vaticana,  Vatican City State, Museo Nazionale Antartide, 
Siena, Italy.

Finally, the  fact that pyrrhotite is magnetic (magnetized) should come as no 
surprise.   Martian meteorites especially suspected of being from certain 
regions of Mars  contain this mineral, and as a matter of fact Mars (Geo)ologists 
have speculated  that certain less magnetic areas on the Martian surface were 
unoriented as a  result of impacts, etc...  That's another good reason npot 
to &#(*#  with the magnetization of your Mars rocks.  That tidbit of 
information in  the magnetism just might tell you what part of a planet your rock is 
from.   Or for that matter what part of the Rumuruti parent body...

Saludos,  Doug

==================
En un mensaje con fecha 05/30/2005 6:29:53 PM Mexico Daylight Time,  
Altmann at Meteorite-Martin.de escribe:
But Tom!

I won't tell the  solution.
Try David Weir's Studies!    http://www.geocities.com/CapeCanaveral/9278/
It is always the first place to  look for answers for questions like yours
now. Simply the best place on  web
and I bed in this respect better than your  books.

Buckleboo!
Martin

----- Original Message ----- 
From:  "Tom Knudson" <peregrineflier at npgcable.com>
To: "met list"  <meteorite-list at meteoritecentral.com>
Sent: Tuesday, May 31, 2005 12:54  AM
Subject: [meteorite-list] "R" help


> Hello List, the list  sure is slow, must mean that some people have lives!
> Anyways, I searched  the internet and my book and can not find an answer to
> this  question.
>   Do "R" chondrites have any metal?  It seems  like the have a tiny bit,
but
> not enough to be visible. Are they  attracted to a magnet at all?
> Thanks, Tom
> peregrineflier  <><