![]() Although the Béréba material is relatively homogeneous ('monomict'), both pyroxene and plagioclase show clouding and other features apparently due to moderately strong shock(s). Like many Eucrites, the meteorite's fundamental mineralogical character was established about 4.5 billion years ago, but some of the Isotope ratios were apparently reset ~ 4 billion years ago by the impact. This 3.70 gram Esquel slice is infused with an abundant amount of Peridot, considering its size. The zircon has been helpful in establishing a chronology of the putative Eucrite parent body. The Esquel Pallasite is considered the 'King of Pallasites' among collectors because of its gem quality Peridot (Olivine) which is prized for jewelry. Accessory phases include a silica polymorph, Ti-Chromite, ilmenite, Troilite, Metal, and Zircon. The pyroxene is apparently mostly pigeonite with exolved ferroaugite: plagioclase is anorthitic. It is in many ways a typical monomict eucrite - its primary constituents are pyroxene and plagioclase which are intergrown with each other. Béréba is the fifth largest of only 34 witnessed eucrite falls but only a kilogram or so remains in the museums listed in the Catalogue of Meteorites (5/e). ![]() After detonations, the Béréba eucrite landed in what is now Burkina Faso. ![]()
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