Chondrite is a stony meteorite that contains chondrules embedded in a fine matrix of the silicate minerals olivine and pyroxene. Les chondrites sont des météorites pierreuses formées de silicates avec quelques éléments métalliques. The rougher portion on the bottom of the photo is where the fusion crust as broken off after it fell. This is one of many fragments of ordinary chondrite from Algeria known as Northwest Africa 869 (L3–6, 2 tons). [8] Only about 200 E-Type chondrites are currently known. Enstatite chondrites (also known as E-type chondrites) are a rare form of meteorite thought to comprise only about 2% of the chondrites that fall on Earth. [8]E-type chondrites are among the most chemically reduced rocks known, with most of their iron taking the form of metal or sulfide rather than as an oxide. The E-chondrite-like meteorite Itqiy is a partial melt residue, resulting from removal of ∼20% partial melt from an enstatite-chondrite-like parent body (Patzer et al., 2001, Keil and Bischoff, 2008). The definition of a chondrite has expanded recently with the discovery in Antarctica and the Sahara Desert of extraordinary meteorites with chondrules 10-100 μm in size, and chondrites so rich in metallic Fe,Ni that they were initially classified as iron meteorites with silicate inclusions. Notice that it is smooth with no holes. from different chondrites, enstatite chondrite (EC) chondrules are dominated by Fe-poor enstatites ( ∼ 70% ) , and also contain some olivine, mesostasis, and … Thermal metamorphism is a broad topic without sharp boundaries. chondrite classes, and its effects play a major role in the classification schemes that have been developed for chon-drites (see Weisberg et al., 2006). Enstatite chondrites (also known as E-type chondrites) are a rare form of meteorite thought to comprise only about 2% of the chondrites that fall on Earth. On the top, the fusion crust is still intact. So one needs to remember that the term 'inclusion' is a term of art — it almost always represents an amalgam of fact, experience, implicit hypotheses, and individual hunches. Definition resolution of such interesting, but difficult questions is, of course, sometimes well nigh impossible at the present time. [1]E-type chondrites are among the most chemically reduced rocks known, with most of their iron taking the form of metal or sulfide rather than an oxide. [1] Only about 200 E-Type chondrites are currently known. The low bulk chlorine content of Itqiy is consistent with chlorine being removed in the plagioclase–enstatite melt fraction. Enstatite chondrite meteorites are rare today, but they may have been Earth's basic building blocks. About 85 percent of all meteorites are chondrites. The discoveries of the Bench Crater carbonaceous chondrite and Hadley Rille enstatite chondrite among returned lunar samples and the identification of the Meridiani Planum iron on Mars demonstrate that foreign objects, analogous to meteorites found on Earth, can arrive intact on the surfaces of other planetary bodies. For example, heating due to the passage of a shock wave potentially affects components of a meteorite A study finds these meteorites contain a surprising … EL3/6, impact-melt breccia ‘Fossil’ or ‘Paleo’ Meteorite (EL6/7 in MetBull 91; aubrite pairing in MetBull 92) Revised classifications have been submitted to NomCom and MetBull click on photo for an enlarged view Purchased August 2005 27° 30′ N., 12° 30′ W. 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