An Article In Meteorite-Times Magazine
by Robert Verish
Oum Rokba v. NWA 400
Oum Rokba v. NWA 400
Oum Rokba may soon be renamed as NWA 400
In September of 2000, several hundred chondritic stones with a total known weight of around 100 kilos were exported out of Morocco. All of these stones were found by a Berber native turned meteorite hunter a few kilometers from an Oasis named Oum Rokba. Although these stones came in various shapes and sizes, their exteriors all exhibited a unique and uniform appearance. This uniform appearance gave the confidence to assume that all of these stones were paired to each other. Subsequently, this meteorite was classified by UCLA as an H5 chondrite and eventually nearly all of the stones were marketed under the name "Oum Rokba".
Even though the importer of this meteorite submitted an appropriate type specimen, and had it classified, a request for a proposed name was never submitted to the Nomenclature Committee (NomComm) of the Meteoritical Society. Nevertheless, many meteorite collections contain specimens that are labeled "Oum Rokba". To this day, many chondritic stones continue to be marketed with labels that use the name "Oum Rokba (H5)".
And as is usual in these situations, several stones that are similar-looking to "Oum Rokba" have had provisional NWA numbers assigned to them. Most notable among these unclassified chondrites is the 10kg (TKW) of NWA 400.
But recently, the NomComm has received a request to issue a (new) NWA number for this classified meteorite in order to get the type specimen properly added into the UCLA Collection with a formally approved name that would eventually appear in the Meteoritical Bulletin.
What would be preferable, is that an existing provisional NWA number be formally approved by the NomComm and that when this number appears in the Meteoritical Bulletin (Database) the description would include a mention that "Oum Rokba is a synonym" for this meteorite. Preferably, this "existing provisional NWA number" would have a large TKW and would have been widely marketed. NWA 400 is just that "existing provisional NWA number". Collections with specimens labeled as "NWA 400" would not need to be relabeled as a result of this change. Specimens that are labeled as "Oum Rokba" would find when searched in the Meteoritical Bulletin Database that "Oum Rokba is a synonym for NWA 400" (should this phrase be included in the description for NWA 400) and then could be relabeled accordingly. Future versions of meteorite catalogues could then list this meteorite as, "Oum Rokba v. NWA 400".
Of course, in order for all of this to happen it will be necessary for UCLA to show that NWA 400 is paired to "Oum Rokba". It would be preferable that UCLA classifies a specimen of NWA 400, and then conducts the comparison with their type specimen of "Oum Rokba".
If you have any information pertaining to either NWA 400 or to Oum Rokba that would be helpful in getting either of these names approved by the Nomenclature Committee, or if you have a strong opinion as to which of these of these names should be approved, you should contact the Editor of the Meteoritical Bulletin, Dr. Michael K. Weisberg and submit your information or opinion.
Should the time come that the NomComm formally approves a name for the meteorite that is popularly known as "Oum Rokba" / NWA 400, then this web page will be updated in order to reflect that change in status.
REFERENCES:Tucson Show Report 2002 - From a search on Google for "Oum Rokba". (Scroll down to Auction Lot #100).
Image of a large Oum Rokba individual - From an image search on Google for "Oum Rokba".
Image of an Oum Rokba specimen in a private collection - From an image search on Google for "Oum Rokba".
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