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CB chondrites occur in two types, both of which are similar to CH chondrites in that they are very depleted in volatile elements and rich in metal. CB a (subgroup a) chondrites are coarse grained, with large, often cm-sized chondrules and metal grains and almost no refractory inclusions. Chondrules have unusual textures compared to most other ...
Again, different kinds of chondrites contain different ranges of chondrule sizes: they are smallest in CH, CM, and CO chondrites (see meteorite classification), moderately large in CR, CV, L, LL, and R chondrites, and largest in some CB chondrites (see table). Other chondrite groups are intermediate between these.
"H" stands for "high metal" because CH chondrites may contain up to as much as 40% of metal. [16] That makes them one of the most metal-rich of any of the chondrite groups, second only to the CB chondrites and some ungrouped chondrites such as NWA 12273. The first meteorite discovered was ALH 85085. Chemically, these chondrites are closely ...
C-chondrites in general, and CM chondrites among them, have low densities for meteorites. CMs are slightly more dense (~2.1 gram/cc) than the CIs, but less dense than CO and other C-chondrites. [ 15 ] [ 16 ] This is due to a combination of brecciation (rock lithified from fragments of prior rocks) [ 17 ] including porosities [ 2 ] and ...
Carbonaceous chondrites compose about 4 percent of all meteorites observed to fall from space. Prior to 1969, the carbonaceous chondrite class was known from a small number of uncommon meteorites such as Orgueil, which fell in France in 1864. Meteorites similar to Allende were known, but many were small and poorly studied. [3]
Ordinary chondrite NWA 3189 sliced. Field of view c. 2.2 cm across. NWA 3189 has been classified as an LL3.2–3.4 ordinary chondrite ("LL" means very low total iron content; "3" refers to well-preserved chondrules – the rock has not been subjected to metamorphism intense enough to disrupt the chondritic texture).
The L type ordinary chondrites are the second most common group of meteorites, accounting for approximately 35% of all those catalogued, and 40% of the ordinary chondrites. [1] The ordinary chondrites are thought to have originated from three parent asteroids, with the fragments making up the H chondrite, L chondrite and LL chondrite groups ...
Nagy B, Claus G, Hennessy DJ (1962) Organic Particles Embedded in Minerals in Orgueil and Ivuna Carbonaceous Chondrites. Nature 193 (4821) p. 1129; Fitch FW, Anders E (1963) Organized Element - Possible Identification in Orgueil Meteorite. Science 140 (357) p. 1097