Arsenic in meteorites and tektites

The chemistry and mineralogy of meteorites suggest that many of them are remnants of condensates from the Solar Nebula or fragments of asteroids and planetesimals that once inhabited the early solar system (Faure, 1998, 105 Wasson and Kallemeyn, 1988, 536). The mineralogy of meteorites also indicates that some planetesimals were once large and hot enough to differentiate metallic cores and other internal layers (Faure, 1998, 105). A number of meteorites even reveal the existence of liquid water in the interiors of some planetesimals (Chapman, 1999, 341). 

Meteorites are generally divided into three broad groups according to their chemistry and mineralogy that is, stones, stony irons, and irons (Chapman, 1999, 353 Dalrymple, 1991, 264). As the name implies, stony irons are meteorites with intermediate compositions between irons and stones (Dalrymple, 1991, 264). Stones mostly consist of carbonate minerals, magnesium- and iron-rich silicates, and/or other nonmetallic 

Of all meteorites, the volatile-rich Cl chondrites are believed to most closely resemble the chemistry of the solar system (Wasson and Kallemeyn, 1988 Palme and Jones, 2004). Chondrites directly condensed from the Solar Nebula (Wasson and Kallemeyn, 1988, 536). Large numbers of chondrites are believed to have agglomerated into the planetesimals, which eventually formed the inner planets of our solar system (Wasson and Kallemeyn, 1988, 536). 

Irons largely or entirely consist of nickel-iron alloys. At least some of them are probably the remains of core materials of the planetesimals that once existed in the solar system (Dalrymple, 1991, 274). Based on their chemistry, irons are subdivided into several types, which are usually identified with Roman numerals and letters (IAB, IC, IVA, etc.) Krot, Keil and Goodrich (2004) discusses a common classification system for irons. 

Tektites are glass spheroids, which cover parts of North America (about 35-million-years old), central Europe (about 15-million-years old), western Africa (about 1.1-million-years old) and Australia-Asia (about 780000 years old). Most tektites are less than 1 mm in diameter (microtektites), although some are centimeter-sized (Koeberl et al., 1997, 1745). Researchers generally believe that tektites represent terrestrial surface materials that were melted and ejected high into the atmosphere because of large meteorite impacts (Koeberl et al., 1997, 1746). 

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