Achondrites properties

The aubrites (enstatite achondrites) are clearly closely related to the enstatite chondrites, discussed earher. They also share the property of being highly reduced, and have identical oxygen isotopic compositions (Clayton et al., 1984). Experimental studies by McCoy et al. (1999) show that partial melting of an E-chondrite can yield aubiitic material by removal of a basaltic melt and a metal-sulfide melt. This is the best known instance of a genetic connection between chondrites and achondrites. 

Achondrites as a whole show one curious property when compared to the total range of meteorite types—chondrites, achondrites, stony irons, and irons. Many of the achondrite types... 

The trapped noble gases in ureilites are part of the properties that make this class of achondrites enigmatic, as they often have been called because they combine properties of primitive and not-so-primitive meteorites. Among the primitive ones is the high abundance of noble gases that approach or in some cases even surpass those found in the most primitive chondrites (Gobel et al. 1978). This, as well as the similarity in isotopic composition and elemental abundance pattern to the Q component has repeatedly been cited as evidence for a close relationship between those two components (Ott et al. 1984, 1985b Busemann et al. 2000). 

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