Inductively coupled plasma-mass spectrometry (ICP-MS) has been used to determine the abundance of trace elements in 32 international geostandards. Half a gram of the sample was treated with HClO₄-HNO₃-HF to bring the elements in the sample into solution and finally made up to 100ml. It was possible to determine nearly 40 trace and ultra-trace elements in samples simultaneously by aspirating the above acid digests after a 5-fold dilution.
The results obtained with the present facility show high to acceptable precision and are in good agreement with the reported data for 37 elements (Li, Be, Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Mo, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, Pb, Bi, Th and U). The degree of the agreement for each of the analyzed elements was evaluated by the correlation coefficients and the standard errors of the regression coefficients of the regression lines for ICP-MS data vs. working values. Results with larger relative standard deviations and discrepancies from previously reported data were obtained for another 3 elements (Ga, Ge and W).

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Nepheline component (NaAlSiO₄, 20 wt.%) was added to the join diopside (CaMgSi₂O₆)-acmite (NaFeSi₂O₆) and the phase relations were determined at 10^-12 atm ƒO₂ and 1, 050-1, 300°C. The liquidus lines for wustite and clinopyroxene cross each other at about 1, 160°C and the composition of Di₂₄Ac₅₆Ne₂₀. The field of clinopyroxene+wüstite+liquid extends from Di₁₅Ac₇₅Ne₂₀ to Di₄₀Ac₄₀Ne₂₀ at 1, 050°C. In the Di-rich region the phase relations are complicated. Olivine appears as second phase, but disappears at lower temperatures (<1, 100°C). Melilite (<1, 200°C ) and nepheline (<1, 150°C) are present at lower temperature region and coexist with olivine and/or clinopyroxene.

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