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Brearley Institute of Meteoritics, Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131, USA Received 26 July 1994; accepted 3 March 1995. Abstract The petrological and mineralogical characteristics of the unusual CM2 chondrite, Bells, have been investigated in detail by scanning electron microscopy (SEM), electron microprobe analysis (EPMA), and transmission electron microscopy (TEM).
Bells is a highly brecciated chondrite which contains few intact chondrules, a very low abundance of refractory inclusions, and is notable in having an unusually high abundance of magnetite, which is disseminated throughout the fine-grained matrix.
magazine, Nov., 1996 - cover story) Scientists believe the E chondrites come from within the orbit of Mercury (as certain constituents could only have formed in heat that close to the sun) Many feel Mercury, itself is the actual body of origin for the Es. "Rubin and Scott argue effectively for two distinct impact events with an intervening period of brecciation through meteoroid bombardment to explain the diamonds and partially melted clasts...." (Kempton, 1996) Besides for all that, it is a VERY zappy meteorite visually. That is what I will offer it for here 700- .695g(EUC unbr) Found Morocco, 2000 30° 33' N., 4° 54' W. Later, a second, 400g stone was recovered which was originally thought to be a new Chassignite. Still, for the first ten years after the fall, material was readily available to the private collector.
0/g : Acapulcoites are named after this unique meteorite - and there are precious few of them - and they are ALL small. However, Rubin of UCLA identified it as a second stone of Agoult. Ongoing research on this unique, unbreciated eucrite will undoubtedly yield interesting information. Since that time, however, whole specimens have become increasingly difficult to obtain.
This has resulted in the preferential dissolution of Fe-rich chondrule olivines, which are now completely absent in Bells although present in other CM chondrites. This is the most popular material I have ever sold.
Pieces were scattered over a wide area..fortunately no-one was hurt....
It also contains the oldest material in the solar system as well as diamonds. The author devotes five pages to Allende and the text contains multiple photographs of this stone throughout the book.
Few specimens have been recovered in recent years due to the extensive initial field collecting and subsequent thorough combing of the area by local inhabitants for sale to collectors. Among the other many interesting aspects of Allende, unmanned probes have indicated that the only formation in the solar system which has the same refractive qualities and weight/mass ratio as Allende is Phobos, one of the moons of Mars!
Fragmental olivines and pyroxenes are common and, based on compositional data, appear to have been derived from chondrules as a result of extensive brecciation.
The fine-grained mineralogy of matrix in Bells differs considerably from other CM chondrites and has closer affinities to matrix in CI chondrites.