Trace elements diamond inclusions

The P-type versus E-type paragenetic classification of diamonds based on their inclusions is introduced in Section 2.05.4.1.3. The geochemical basis for this fundamental difference between inclusion types is discussed in review articles by Meyer (1987), Harris and Gurney (1979), Gurney (1989), and Kirkley et al. (1991), summarized in brief here and discussed in the context of newer SIMS trace-element data on inclusions. Meyer (1987) points out the importance of inclusions in diamonds for the study of the mantle. First, inclusions are the chief way to understand the relationship of diamonds to their mantle host lithologies. Second, inclusions often represent pristine, geochemically unaltered samples that are not subject to the chemical re-equilibration and alteration that affects the minerals in xenoliths and macrocry sts. 

Ireland T. R., Rudnick R. L., and Spetsius Z. (1994) Trace elements in diamond inclusions from eclogites reveal hnk to Archean granites. Earth Planet. Sci. Lett. 128, 199—213. 

Pearson D. G. and Milledge H. J. (1998) Diamond growth conditions and preservation inferences from trace elements in a large garnet inclusion in a Siberian diamond. Extended Abstracts of 7th Int. Kimb. Conf., Cape Town, pp. 667-669. 

Shimizu N. and Richardson S. H. (1987) Trace element abudance patterns of garnet inclusions in peridotite suite diamonds. Geochim. Cosmochim. Acta 51, 755-758. 

Stachel T. and Harris J. W. (1997) Diamond precipitation and mantle metasomatism evidence from the trace element chemistry of silicate inclusions in diamonds from Akwatia, Ghana. Contrib. Min. Petrol. 129(2-3), 143-154. 

In deeper samples, the trace-element geochemistry observed in garnet inclusions in diamonds has been attributed to carbon-bearing fluids (e.g., Stachel and Harris, 1997 Wang et al., 2000 Dobosi and Kurat, 2002), although the oxidation state of the fluid (CO2- versus CH4-rich) remains open to debate. 

Bulanova G. P., Griffin W. L., Ryan C. G., Shestakova O. Y., and Barnes S.-J. (1996) Trace elements in sulfide inclusions from Yakutian diamonds. Contrib. Mineral. Petrol. 124, 111-125. 

LA techniques using UV YAG-Nd laser (wave length - 266 nm) for trace analysis of natural and artificial diamonds and for detenuination of chemical composition of micro-inclusions (5 - 50 p.m ) in natural quartzites were developed by ICP-MS ELEMENT (Germany). 

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