Chondrites mineralogic properties

Few comprehensive reviews of the origin and properties of chondritic components have appeared since Kerridge and Matthews (1988). Exceptions include a comprehensive review of chondrite mineralogy (B J, 1998), an edited book on chondrules and their origins (Hewins et al, 1996), and several reviews on chondrules and CAIs (Hewins, 1997 Rubin, 2000 Jones et al., 2000a Ireland and Fegley, 2000). 

The detailed CL trends displayed by the type 3 ordinary chondrites are therefore a unique means of determining not only the mineralogical factors affecting TL sensitivity, but they also provide a new means of examining the compositional (by complementary electron microprobe analysis) and structural (i.e. petrographic) changes associated with metamorphism-induced changes in CL properties. In the next few sections we summarize the CL properties of the ordinary chondrites. 

Weisberg et al. 2006 Chapter 1). The key point is that subdivision of chondrites is based on differences in the basic chemical, mineralogical, and textural properties that are unique to each class. Chondrites also record difference in redox conditions before and during their accretion providing important clues to disk environments and properties such as oxygen, carbon, and sulfur abundances in these regions. 

Conventionally, a chondrite group is defined as having a minimum of five unpaired chondrites of similar mineralogy, petrography, bulk isotopic properties, and bulk chemical compositions in major, nonvolatile elements. According to this definition, K chondrites could be considered as a grouplet there are only two known K chondrites (see K (Kakangari-like) chondrites). 

CR clan chondrites. The CR clan includes a wide diversity of chondritic meteorites that share sufficient mineralogic and isotopic properties in common to be considered genetically related (Weisberg et al, 1995) it includes the CR and... 

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