Sixty-three rocks of the pelitic Devonian Littleton formation of New Hampshire have been analyzed spectrographically for trace elements. The samples represent all grades of metamorphism from shales to sillimanite schists and gneisses. The average concentrations and standard deviations in ppm are: Ga, 19, 6.3; Cr, 110, 33; V, 120, 39; Li, 110,104; Ni, 64, 26; Co, 18, 6.6; Cu, 18, 18; Sc, 14, 7.4; Zr, 200, 73; Y, 45, 20; Sr, 710, 310; Pb, 24, 12. Be, Mo, Sn, La, and Ag were usually below the sensitivity limits of 30, 10, 20, 100, and 1 ppm respectively. Ba almost always exceeds 1000 ppm.

Figures for individual analyses were grouped according to low- medium- or high-grade metamorphism. Statistical tests show a rather wide range in original composition, which suggests that it is unwise to deduce composition changes from a few analyses. The analyses, however, show that the concentration of most elements remained constant during regional metamorphism. Ni and Cu show a slight decrease, and Li and Pb a well-defined increase of the order of 100 per cent accompanying the metamorphism. This increase is a metasomatism at the trace-element level, which probably accompanies the potash-metasomatism encountered by Billings in the same formation.

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