This story began for me on August 3th 2009, when I received an email including photographs, from a Moroccan meteorite dealer I had several satisfying deals with before:
"I Have a fresh broken chondrite weighs 315g found in a place named Jbel Elfgah in Morocain desert between the city of Smara
( city in south of Morocco) and Mouritania borders. The nomade who found te stone broke it in 3 fragment."
|(I was kindly provided permission to show
you his original text and photographs here.)
The photographs attached to the email showed three fragments of a broken stone which looked remarkably fresh. I was interested, and it didn't take long to come to a deal.
When I received the fragments, I was even more impressed by their freshness. I had seen some really fresh NWA's before, but never like this. Below some photographs of the fragments.
"Could this be a recent Fall?" passed through my mind.
"And if so, wouldn't it be my responsibility, to try to have this checked as soon as possible, instead of storing it away with the rest of my collection?"
I had some experience with having meteorites classified, but determination of the terrestrial age would need more than the standard procedures. I turned to meteoritecentral's "Meteorite-list" for guidance and advice. This request resulted in many kind reactions and offers to help, and finally resulted in a contact with Dr. Beda Hofmann (Natural History Museum Bern, Switzerland).
The classification specimen before shipping to Switzerland.
Hofmann offered to do the classification job,
including gamma-spectroscopy with the help of Dr. P. Weber (Laboratory
for High Energy Physics, University of Bern, Switzerland), to determine
the elapsed time since the meteorite fell.
Gamma-spectroscopy concerns the measurement of short-lived radionuclides.
Several fresh falls with known fall date were used as a reference. The activity of the cosmogenic isotopes therein could be calculated back to the date of the fall. The mean activity of a number of short-lived isotopes in the fresh falls were taken and compared with the activity ratio in this fresh find/fresh falls. From that the fall date could be calculated.
Gamma-spectroscopy data in general are treated in a number of papers, e.g. for recent falls:
Itawa Bhopji (L3-5) chondrite regolith breccia: Fall, classification, and cosmogenic records: http://adsabs.harvard.edu/abs/2002M%26PS...37..549B
Spectacular fall of the Kendrapara H5 chondrite:
After the finder of the 314g stone was urged to look for more stones, additionally a 91g stone was found in September or October 2009. This stone was offered to me by the same Moroccan dealer on October 7th 2009.
The 91g stone, found a few months later than the first one, shows first signs of weathering on the fusion crust and on a broken edge. It is covered by a somewhat thicker fusion crust than the three fragments.
Below some photographs of this second find.
Note: This specimen is not part of my collection anymore.
an effort to find out if these stones belonged to an observed Fall, I
first tried to gain information with respect to the find
"Jbel Elfgah" didn't show up in any map I could find on the internet. I contacted my Moroccan dealer, and together we started a quest for a map with the location of the find, and the name of the nomad who found the original stone.
My dealer bought the stone from a Moroccan supplier who bought it from the finder. So no direct line to the finder existed. We had to communicate through my dealer's supplier.
To make a long story short, after two to three months we found out that the find was made further south than we had first assumed, and that the find location was locally known as "Gour Lafkah", not "Jbel Elfgah", and was situated in Western Sahara.
"Jbel" translates to mountain, hill or slope, as does "Gour".
My dealer wrote me "Gour mean mountain in Alhassania dialect the Arabic dialect which use the people in Morocan desert (south of Morocco) ."
"Lafkah" was phonetically written down as "Elfgah".
Regrettably the finder of the stones preferred to stay anonymous.
My Moroccan dealer kindly sent me the map he received from his supplier.
Note: In this webpage I'm referring to "my Moroccan dealer", as he prefers to stay anonymous. Classifier Dr. Beda Hofmann knows who this well known-dealer is though.
At the beginning of January 2010, the classification write-up was completed, and the results were submitted to the NomCom of the Meteoritical Society. The classification results are (http://www.lpi.usra.edu/meteor/metbull.php?code=56103):
Petrography: Chondrules are poorly delineated and strongly recrystallized. Plagioclase grains are up to 0.2 mm in size. Troilite shows characteristic twinning lamellae. Besides dispersed grains, chromite and ilmenite form inclusions in iron metal. Cu metal is present at troilite-iron metal contacts.
Geochemistry: Electron microprobe analysis yielded olivine Fa23.3 (Fa22.2 by XRD), pyroxene Fs20.0Wo1.0. Cosmogenic radionuclides: (Patrick Weber, Laboratory for High Energy Physics, University of Bern): Gamma-spectroscopy performed in September 2009 showed the presence of the following short-lived radionuclides: 46Sc, 54Mn, 57Co, 22Na, 26Al. The 22Na/26Al activity ratio of 1.3 is in the range of recent falls. By comparison with the mean activities of 57Co, 51Cr, 54Mn and 46Sc at the time of fall of five other recent falls, a terrestrial age of 202±14 days (before Sept. 20, 2009) is estimated, indicating a fall in February or March 2009.
Classification: Ordinary chondrite (L6), shock stage S3, no weathering (W0).
This meteorite fell in 2009!
A fresh "Fall" turning up through the NWA Nomad and dealers network.
Because the fall of this meteorites was not witnessed, it could not be accepted by the NomCom as a Fall. And because the finder of the stones prefers to stay anonymous, it can't have a proper name either.
All this resulted in a meteorite known to have fallen in 2009, registered under an NWA number. Still pretty special.
One could criticize the commercialized situation, concerning the collecting of meteorites in the NWA countries, for the lack of openness and scientific awareness, and from that the loosing of geographic information.
I think however, that without the continuous dedicated work of Nomads and Moroccan dealers, this beautiful fresh meteorite probably would have never turned up. And for sure not with this fresh appearance.
Many thanks go to the Nomads and dealers in Morocco and other NWA countries who made this beautiful fresh find possible.
A little "off topic":
My family noticed my enthusiasm about this fresh stone, and on father's day 2010 I received a very special present.
A sheet of stamps picturing the Main Mass. Isn't that just great? :
(Note: in The Netherlands it's possible to have official stamps made with one's own photographs.)
Both stones have their own collection webpage.
Links to these are: 314g and 91g
Finally a photograph of the 314g fragments, minus the classification specimen, as they are stored today.
Safely protected against moisture, in their own sealed glass dome